177Lu-DOTA-EB-TATE – Long-lasting radionuclide therapy for advanced neuroendocrine tumors proves effective

For your information only. In the News.

Since PRRT was formally approved last year in USA and Europe (and other places), it’s triggered a whole mini-industry in PRRT variants or enhancements. An interesting study from China, a country starting to become very active in the NET world. I guess they have been active for some time given that I’ve seen their NET experts presenting at the last 2 years of ENETS in Barcelona.  In this particular study, there is linkages to the Laboratory of Molecular Imaging and Nanomedicine, NIBIB/NIH, Bethesda, Maryland in USA.

This is news of a first-in-human study presented at the 2018 Annual Meeting of the Society of Nuclear Medicine and Molecular Imaging (SNMMI) which demonstrated the benefits and safety of a new, long-lasting type of radionuclide therapy (PRRT) for patients with advanced, metastatic neuroendocrine tumors (NETs) – 177Lu-DOTA-EB-TATE. 

How is this different from the current PRRT standard – Lutathera?

“Lu-DOTA-EB-TATE is a “three-in-one” therapeutic compound, with an octreotate peptide to find the tumor, an ‘Evans blue motif’, which uses endogenous albumin as a reversible carrier to effectively extend the half-life in the blood and substantially increase targeted accumulation and retention within the tumor, and a therapeutic radionuclide to kill the tumor cells, to finally provide effective treatment of NETs,”  …….. explains Shawn(Xiaoyuan) Chen, PhD, senior investigator, of National Institute of Biomedical Imaging and Bioengineering at the National Institutes of Health , Bethesda, Maryland.

Lutathera-177 (177Lu)-DOTATATE (trade name Lutathera), a peptide receptor radionuclide tharapy (PRRT) with radiolabeled somatostatin analogues (peptides), was recently approved by the USA FDA and the EMA for the treatment of somatostatin receptor positive NETs. It is the therapeutic part of a nuclear medicine theranostic pairing. Gallium-68 (68Ga)-DOTATATE is the diagnostic agent used in  PET/CT scans that first locates and marks the lesions for follow-up with targeted PRRT delivery directly to the tumor cells which express high levels of somatostatin receptors (SSTRs). Because the PRRT binds to receptors expressed by the tumor cells, healthy cells are unharmed. However, the peptide quickly clears from the blood through the kidneys limiting the accumulation of radioactivity within tumors and making additional treatment cycles necessary to provide the therapeutic dose.

177Lu-DOTA-EB-TATE.  This first-in-human, first-in-class, Phase I trial (ID: NCT03308682) investigated the safety and dosimetry of a novel long-lasting radiolabeled somatostatin analogue that adds an albumin-binding Evans blue (EB, an azo dye) derivative to 177Lu-DOTATATE. Albumin, the most abundant plasma protein in human blood, is a natural transport protein and has a long circulatory half-life.  This is an open-label, non-controlled, non-randomized study.

For the study, conducted in collaboration with researchers at the U.S. National Institute of Biomedical Imaging and Bioengineering, 8 patients (6 men and 2 women ranging in age from 27 to 61 years old) with advanced metastatic neuroendocrine tumors were recruited from Peking Union Medical College Hospital and the Chinese Academy of Medical Sciences in Beijing, China.

Each patient underwent whole-body 68Ga-DOTATATE PET/CT. Five of the patients then accepted intravenous injection with a single dose of 0.35-0.70 GBq of 177Lu-DOTA-EB-TATE within one week, and were monitored at 2, 24, 72, 120 and 168 hours after 177Lu-DOTA-EB-TATE administration with serial whole-body planar and single photon emission computed tomography (SPECT)/CT images acquired. The other 3 patients accepted a dose of 0.28-0.41 GBq of 177Lu-DOTATATE and were monitored at 1, 3, 4, 24 and 72 hours with the same imaging procedures. Complete physical examinations, including vital signs, blood count, biochemistry, and immunology analyses were performed immediately before and 1, 3, and 7 days, as well as 3 months, after treatment.

Administration of 177Lu-DOTA-EB-TATE was well tolerated, with no adverse symptoms reported throughout the procedure and follow-up. The total effective dose equivalent and effective dose were 0.2048 ± 0.1605 and 0.0804 ± 0.0500 mSv/MBq for 177Lu-DOTA-EB-TATE and 0.1735 ± 0.0722 and 0.0693 ± 0.0317 mSv/MBq for 177Lu-DOTATATE. The liver, kidneys, bone marrow and total body received slightly higher doses (mGy/MBq) with 177Lu-DOTA-EB-TATE than with 177Lu-DOTATATE, while the spleen received lower doses with 177Lu-DOTA-EB-TATE. Blood clearance of 177Lu-DOTA-EB-TATE was also slower. Most importantly, 177Lu-DOTA-EB-TATE lasted in the tumors more than 4 times longer than 177Lu-DOTATATE.

Jingjing Zhang and Zhaohui Zhu of Peking Union Medical College Hospital point out, “By introducing an albumin binding moiety, this long-lasting radiolabeled somatostatin analogue has remarkably enhanced uptake and retention in SSTR-positive tumors, which is important to increase the therapeutic efficacy in patients. With proper selection of patients with advanced metastatic neuroendocrine tumors, 177Lu-DOTA-EB-TATE has great potential to be a highly effective treatment, while providing a safe dose with less frequency of administration than is possible with 177Lu-DOTATATE.”

FIGURE: SPECT/CT of a 45-year-old male patient with advanced NETs and multiple liver metastases – persistently retained in the tumors after 168 hours

Scans were done at 2, 24, 72, 120 and 168 hours after the administration of 177Lu-DOTA-EB-TATE. The radiopharmaceutical cleared from the blood pool over time and persistently retained in the tumors (arrows). Credit: J Zhang et al., Peking Union Medical College Hospital, Beijing, China; X Chen et al., Laboratory of Molecular Imaging and Nanomedicine, NIBIB/NIH, Bethesda, MD

Sources:

Abstract 118: “Safety, Pharmacokinetics and Dosimetry of a Long-lasting Radiolabeled Somatostatin Analogue 177Lu-DOTA-EB-TATE in Patients with Advanced Metastatic Neuroendocrine Tumors: A Phase 1 First-in-human Study,” Jingjing Zhang, MD,PhD, Yuejuan Cheng, MD,Hao Wang, MD, Jie Zang, PhD, Fang Li, MD, Chunmei Bai, MD, and Zhaohui Zhu, MD, Peking Union Medical College Hospital; Gang Niu, MD, Orit Jacobson, PhD4, and Xiaoyuan Chen, PhD, U.S. National Institutes of Health, Bethesda, MD. SNMMI’s 65th Annual Meeting, June 23-26, Philadelphia.  Link to SNMMI Abstract

Other articles in this series:

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Ronny

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Remember ….. in the war on Neuroendocrine Cancer, let’s not forget to win the battle for better quality of life!

PRRT – The Sequel? – Clinical trial of Targeted Alpha-emitter Therapy (TAT) –  212 Pb-AR-RMX

Radioimmunotherapy

In 2018, RadioMedix Inc. and Areva (parent company Orano Med) initiated the Phase 1 trial for AlphaMedixTM in patients with somatostatin receptor (SSTR) positive Neuroendocrine Tumors (NETs) – an NIH supported trial.

AlphaMedixTM is composed of a somatostatin analogue radiolabeled with 212Pb, an isotope used for Targeted Alpha-emitter Therapy (TAT).  This open-label, dose escalation study’s objective is to determine safety, bio-distribution, and preliminary effectiveness of 212 Pb-AR-RMX in adult patients with differentiated (sic) NETs. “Targeted Alpha-emitter Therapy (TAT) is the wave of the future in nuclear oncology and has a tremendous potential to treat patients with NET and overcome some of the limitations of current Peptide Receptor Radionuclide Therapy (PRRT)” said Dr. Ebrahim S. Delpassand, Chairman and CEO of RadioMedix, sponsor of the trial. They further announced on 21 Feb 2018 that the first patients had undergone some treatment.

The funding for Phase 2 was granted by NIH on 22 Jan 2019.

What is Targeted Alpha-emitter Therapy?  Targeted Alpha Therapy is based on the coupling of alpha particle emitting radioisotopes to tumour selective carrier molecules, such as monoclonal antibodies or peptides. These molecules have the ability to selectively target tumour cells even if they are spread throughout the body. They recognize the targeted cancer cells through antigens that are expressed on the cell surface and can bind selectively to these cells, similar a key fitting into a lock. In targeted alpha therapy these carrier molecules serve as vehicles to transport the radioisotopes to the cancer cells. This is called the “magic bullet” approach. Radioisotopes that emit alpha particles seem particularly promising to selectively destroy cancer cells. Alpha particles have a high energy in the range of 5-9 MeV and at the same time a very short path length in human tissue below 0.1 mm, corresponding to less than 10 cell diameters. Consequently, the use of alpha emitters allows the specific targeting and killing of individual malignant cells, while minimizing the toxicity to surrounding healthy tissue. Extracted from EU Science Hub

According to the clinical trials document, this drug addresses an unmet need in the field of peptide receptor radionuclide therapy (PRRT) for NETs. Substitution of an alpha emitter (²¹²Pb) for the beta emitters currently being used (i.e., 177Lu or 90Y) will provide significantly higher Linear Energy Transfer (LET) and a shorter path length. Higher LET particles should cause more tumor cell death. Shorter path length should result in less collateral damage of the normal tissue and therefore less side effects for subjects receiving the drug.

What is the difference between PRRT and TAT?  From the scant ‘patient understandable‘ information currently available, it would appear that TAT has the potential to be more targeted and less toxic than PRRT – to me that seems like it would be able to target smaller tumors.  I also noted that TAT is sometimes described as a ‘radioimmuotherapy’ or ‘alpha immunotherpy’, indicating the mechanism of action is significantly different to that of conventional PRRT. It was also described as a ‘Trojan Horse’ which would seem to hint at its immunotherapy credentials.

I noted that TAT is also being studied for use in Prostate Cancer and Leukaemia.

Related articles:

Announcement of Phase 1 Clinical Trial – click here – results to follow.

Funding grant from NIH for Phase 2 – click here

Phase 1 Clinical Trial Document Phase 1 Study of AlphaMedix™ in Adult Subjects With SSTR (+) NET – click here – Phase 2 document to follow.

Areva Med Website – click here

RadioMedix Inc Website – click here

You may also enjoy my articles:

Lutetium Lu 177 dotatate (Lutathera®) – PRRT” – click here.
Expanding PRRT – Trial of 177Lu-Edotreotide (Solucin®) – COMPETE Trial” – click here.
Theranostics – a find and destroy mission” – click here
Ga68 PET Scans – into the unknown” – click here

Thanks for reading

Ronny

I’m also active on Facebook.  Like my page for even more news.  I’m also building up this site here: Ronny Allan

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Remember ….. in the war on Neuroendocrine Cancer, let’s not forget to win the battle for better quality of life!

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ASCO 2017 – Let’s talk about NETs #ASCO17

ASCO (American Society of Clinical Oncology) is one of the biggest cancer conferences in the world normally bringing together more than 30,000 oncology professionals from around the world to discuss state-of-the-art treatment modalities, new therapies, and ongoing controversies in the field.  As Neuroendorine Tumors is on a roll in terms of new treatments and continued research, we appear to be well represented with over 20 ‘extracts’ submitted for review and display.  This is fairly complex stuff but much of it will be familiar to many.  I’ve filtered and extracted all the Neuroendocrine stuff into one list providing you with an easy to peruse table of contents, complete with relevant linkages if you need to read more.  For many the extract title and conclusion will be sufficiently educational or at least prompt you to click the link to investigate further.  Remember, these are extracts so do not contain all the details of the research or study. However, some are linked to bigger trials and linkages are shown where relevant.  I’ve also linked to some of my blog posts to add context and detail.

I’m hoping to capture any presentations or other output from the meeting which appears to be relevant and this will follow after the meeting.  I will also be actively tweeting any output from the live event (for many cancers, not just NETs).

There’s something for everyone here – I hope it’s useful.

68Ga-DOTATATE PET/CT to predict response to peptide receptor radionuclide therapy (PRRT) in neuroendocrine tumours (NETs).  

Conclusions: Objective response to PRRT defines a subset of patients with markedly improved PFS. SUVave 21.6 defines a threshold below which patients have a poor response to PRRT. This threshold should be taken forward into prospective study.

Check out my recent blog discussing ‘Theranostic pairing” – click here

Rohini Sharma 4093
A multicohort phase II study of durvalumab plus tremelimumab for the treatment of patients (PTS) with advanced neuroendocrine neoplasms (NENs) of gastroenteropancreatic (GEP) or lung origin (the DUNE trial-GETNE1601-).

News of a trial – no conclusion included.  However, see trial data NCT03095274

Ignacio Matos Garcia TPS4146
Association between duration of somatostatin analogs (SSAs) use and quality of life in patients with carcinoid syndrome in the United States based on the FACT-G instrument.

Conclusions: The duration of SSA use was positively associated with QoL benefit among CS patients. This may be explained by long-term effectiveness of SSAs or selection bias favoring patients with more indolent disease. Future studies will be needed to distinguish between these possibilities.

Daniel M. Halperin e15693
Association of weight change with telotristat ethyl in the treatment of carcinoid syndrome.

Conclusions: The incidence of weight gain was dose-related on TE and was greater than that on pbo. It was possibly related to a reduction in diarrhea severity, and it may be a relevant aspect of TE efficacy among patients with functioning metastatic NETs. Clinical trial information: NCT01677910

See my blog post Telotristat Ethyl

Martin O Weickert e15692
Blood measurements of neuroendocrine tumor (NET) transcripts and gene cluster analysis to predict efficacy of peptide radioreceptor therapy.

Conclusions: A pre-PRRT analysis of circulating NET genes, the predictive quotient index comprising “omic” analysis and grading, is validated to predict the efficacy of PRRT therapy in GEP and lung NETs.

Lisa Bodei 4091
Capecitabine and temozolomide (CAPTEM) in neuroendocrine tumor of unknown primary.

Conclusions: CAPTEM shows activity in neuroendocrine tumor of unknown primary. Currently FDA approved treatment options for grade I and grade II GI NETs includes somatostatin analogs and everolimus. Both of which are cytostatic and of limited use in case of visceral crisis or bulky disease where disease shrinkage is required. CAPTEM should be considered for grade II NETS of unknown primary.

Aman Chauhan e15691
Clinical and epidemiological features in 495 gastroenteropancreatic neuroendocrine patients in Mexico.

Conclusions: This is the first multi-center study in Mexico. Which reflects the clinical characteristics of the NET_GET. The results differ in their epidemiology from that reported in other countries. However, the clinical and therapeutic results are very similar.

Rafael Medrano Guzman e15687
Effect of lanreotide depot (LAN) on 5-hydroxyindoleacetic acid (5HIAA) and chromogranin A (CgA) in gastroenteropancreatic neuroendocrine (GEP NET) tumors: Correlation with tumor response and progression-free survival (PFS) from the phase III CLARINET study.

Conclusions: These data suggest that serotonin is secreted by nonfunctioning tumors, but does not reach the threshold required for clinical carcinoid symptoms. Monitoring 5HIAA and CgA may be useful during LAN treatment of nonfunctional GEP NETs. Clinical trial information: NCT00353496

Alexandria T. Phan 4095
Final progression-free survival (PFS) analyses for lanreotide autogel/depot 120 mg in metastatic enteropancreatic neuroendocrine tumors (NETs): The CLARINET extension study.

Conclusions: CLARINET OLE suggests sustained antitumor effects with LAN 120 mg in enteropancreatic NETs irrespective of tumor origin, and suggests benefits with LAN as early treatment. Clinical trial information: NCT00842348

Edward M. Wolin 4089
Lanreotide depot (LAN) for symptomatic control of carcinoid syndrome (CS) in neuroendocrine tumor (NET) patients previously responsive to octreotide (OCT): Subanalysis of patient-reported symptoms from the phase III elect study.

Conclusions: Pts showed improvement in CS symptoms of flushing and diarrhea and reduction in 5HIAA levels with LAN treatment, indicating efficacy of LAN regardless of prior OCT use. Transition from OCT to LAN was well tolerated among prior OCT pts in ELECT. Clinical trial information: NCT00774930

Check out my blog post about Lanreotide and Lanreotide vs Octreotide

George A. Fisher 4088
Molecular classification of neuroendocrine tumors: Clinical experience with the 92-gene assay in >24,000 cases.

Conclusions: These findings highlight the utility of molecular classification to identify distinct NET tumor types/subtypes to improve diagnostic precision and treatment decision-making. In addition, significant differences in the distribution of molecular diagnoses of NET subtype by age and gender were identified.

Andrew Eugene Hendifar e15700
Multi-omic molecular profiling of pancreatic neuroendocrine tumors.

Conclusions: In PNETS, multi-omic profiling through the KYT program identified targetable alterations in several key pathways. Outcome data will be explored.

Rishi Patel e15685
Outcomes of peptide receptor radionuclide therapy (PRRT) in metastatic grade 3 neuroendocrine tumors (NETs).

Conclusions: In this poor prognosis G3 NET cohort of whom 77% had received prior chemotherapy, a median OS of 18 months from start of PRRT is encouraging and warrants further study. PRRT is a promising treatment option for patients with G3 NET with high somatostatin-receptor expression selected by SSRI.

Mei Sim Lung e15694
Periprocedural management of patients undergoing liver resection or liver-directed therapy for neuroendocrine tumor metastases.

Conclusions: Occurrence of documented carcinoid crisis was low in this high-risk population. However, a significant proportion of patients developed hemodynamic instability, suggesting that carcinoid crisis is a spectrum diagnosis and may be clinically under-recognized. Use of octreotide was not associated with risk of carcinoid crisis or hemodynamic instability; however, this analysis was limited by our modest sample size at a single institution. There remains a need to establish an objective definition of carcinoid crisis and to inform standardization of periprocedural use of octreotide for at-risk patients.

See my blog on “Carcinoid Crisis” 

Daniel Kwon e15689
Predictive factors of carcinoid syndrome among patients with gastrointestinal neuroendocrine tumors (GI NETs).

Conclusions: By assessing patients with GI NET from two independent US claim databases, this study suggested that patients diagnosed with CS were 2-3 times more likely to be diagnosed with liver disorder, enlargement of lymph nodes, or abdominal mass, than those without CS during the one year prior to CS diagnosis. Future studies using patient medical charts are warranted to validate and interpret the findings. These findings, when validated, may aid physicians to diagnose CS patients earlier.

Beilei Cai e15690
Predictors of outcome in patients treated with peptide radio-labelled receptor target therapy (PRRT).

Conclusions: Radiological progression within 12 months of completion of PRRT is associated with a worse outcome in terms of OS. Patients with greater liver involvement and highest CgA levels are more likely to progress within 12 months of treatment completion. Earlier treatment with PRRT in patients with radiological progression not meeting RECIST criteria may need to be considered. There may be a greater survival benefit if PRRT is given prior to the development of large volume disease.

Dalvinder Mandair 4090
Pre-existing symptoms, resource utilization, and healthcare costs prior to diagnosis of neuroendocrine tumors: A SEER-Medicare database study.

Conclusions: To the best of our knowledge, this is the first population-based study to examine potentially relevant pre-existing symptoms, resource utilization and healthcare costs before NET diagnosis. NET patients were more likely to have certain conditions and incurred higher resource utilizations and costs in the year preceding diagnosis of NET.

Chan Shen 4092
Prevalence of co-morbidities in elderly patients with distant stage neuroendocrine tumors.

Conclusions: This population-based study showed that elderly NET pts have significantly different prevalence of co-morbidities compared to non-cancer controls. The impact of these conditions on survival and therapeutic decisions is being evaluated.

A. Dasari e15699
Prognostic factors influencing survival in small bowel neuroendocrine tumors with liver metastasis.

Conclusions: In patients with SBNET with liver metastasis, higher tumor grade and post-operative chemotherapy increased risk of death. However, resection of the primary tumor along with liver metastasis improves the 5-year OS with complete cytoreduction providing the most benefit.

Nicholas Manguso e15688
Role of 92 gene cancer classifier assay in neuroendocrine tumor of unknown primary.

Role of 92 gene cancer classifier assay in neuroendocrine tumor of unknown primary. | 2017 ASCO Annual Meeting Abstracts

Conclusions: Tissue type ID was able to identify a primary site in NETs of unknown primary in majority (94.7%) of cases. The result had direct implication in management of patients with regards to FDA approved treatment options in 13/38 patients (pNETs, merkel cell and pheochromocytoma).

Aman Chauhan e15696
Surgery in combination with peptide receptor radionuclide therapy is effective in metastatic neuroendocrine tumors and is definable by blood gene transcript analysis.

Conclusions: Radical loco-regional surgery for primary tumours combined with PRRT provides a novel, highly efficacious approach in metastasised NET. The NETest accurately measures the effectiveness of treatment.

Andreja Frilling e15697
The impact of pathologic differentiation (well/ poorly) and the degree of Ki-67 index in patients with metastatic WHO grade 3 GEP-NECs.

Conclusions: Grade 3 GEP-NECs could be morphologically classified into well and poorly differentiated NETs. Additionally, among grade 3 GEP-NECs, there was a significant difference in ranges of Ki67 index between well and poorly differentiated NECs. Higher levels ( > 60%) of Ki67 index might be a predictive marker for efficacy of EP as a standard regimen in grade 3 GEP-NECs.

Check out my blog post on Grading which has incorporated latest thinking in revised grade 3 classification

Seung Tae Kim e15686
Theranostic trial of well differentiated neuroendocrine tumors (NETs) with somatostatin antagonists 68Ga-OPS202 and 177Lu-OPS201.

Conclusions: In this trial of heavily treated NETs, preliminary data are promising for the use of 68Ga-OPS202/177Lu-OPS201 as a theranostic combination for imaging and therapy. Additional studies are planned to determine an optimal therapeutic dose and schedule. Clinical trial information: NCT02609737

Diane Lauren Reidy 4094
Use of antiresorptive therapy (ART) and skeletal-related events (SREs) in patients with bone metastases of neuroendocrine neoplasms (NEN).

Conclusions: SREs in NEN patients with BM were not uncommon, especially in patients with grade 3 NEN and osteolytic metastases. Application of ART did not significantly alter median OS or TTSRE, no subgroup with a benefit of ART could be identified. The use of ART in NEN should be questioned and evaluated prospectively.

Leonidas Apostolidis 4096
Targeted radiopeptide therapy Re188-P2045 to treat neuroendocrine lung cancer

Conclusions: Rhenium Re 188 P2045, a radiolabeled somatostatin analog, may be used to both identify and treat lung cancer tumors. The ability to image and dose patients with the same targeted molecule enables a personalized medicine approach and this highly targeted patient therapy may significantly improve treatment of tumors that over express somatostatin receptor.

Christopher Peter Adams, Wasif M. Saif e20016

Thanks for reading

Ronny
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Recent Progress in NET Management – Positive presentation from Jonathan R Strosberg MD

jonathan-strosbergI recently wrote a blog called Neuroendocrine Cancer – Exciting Times Ahead! I wrote that on a day I was feeling particularly positive and at the time, I wanted to share that positivity with you. I genuinely believe there’s a lot of great things happening. Don’t get me wrong, there’s a lot still to be done, particularly in the area of diagnosis and quality of life after being diagnosed. However, this is a really great message from a well-known NET expert.

In an interview with OncLive, Jonathan R. Strosberg, MD, associate professor at the H. Lee Moffitt Cancer Center in Florida, discussed his presentation on NETs at a recent 2016 Symposium, and shed light on the progress that has been made in this treatment landscape.

OncLive: Please highlight some of the main points from your presentation.

Strosberg: The question I was asked to address is whether we’re making progress in the management of NETs, and I think the answer is unequivocally yes. Prior to 2009, there were no positive published phase III trials.

Since then, there have been 8 trials, 7 of which have reached their primary endpoints. So it’s been a decade of significant improvement. And even though none of these studies were powered to look at overall survival as an endpoint, we’re certainly seeing evidence of improvement in outcomes.

OncLive: What are some of the pivotal agents that you feel have impacted the paradigm in the past several years?

Strosberg: The first group is the somatostatin analogs. We use them to control hormonal symptoms like carcinoid syndrome, but with the CLARINET study, we now know that they substantially inhibit tumor growth.

The next significant drug we use in this disease is everolimus (Afinitor), an oral mTOR inhibitor, which is now approved in several indications based on positive phase III studies. The first was in pancreatic NETs and subsequently, based on the RADIANT-4 trial, it was also approved in lung and gastrointestinal NETs. So that was an important advance.

The next important category of treatment is radiolabeled somatostatin analogs, otherwise known as peptide receptor radiotherapy. The one that’s been tested in a phase III trial is lutetium dotatate, also known as Lutathera. It was tested in patients with progressive midgut NETs and showed a very substantial 79% improvement in progression-free survival, and a very strong trend toward improvement in overall survival, which we hope will be confirmed upon final analysis.

OncLive: Are we getting better at diagnosing and managing the treatment of NETs?

Strosberg: Certainly. I think pathologists are better at making the diagnosis of a NET, rather than just calling a cancer pancreatic cancer or colorectal cancer. They’re recognizing the neuroendocrine aspects of the disease, and doing the appropriate immunohistochemical staining.

We also have better diagnostic tools. We used to rely primarily on octreoscan, and in many cases we still do, but there is a new diagnostic scan called Gallium-68 dotatate scan, also known as Netspot, which has substantially improved sensitivity and specificity. It’s not yet widely available, but it is FDA approved and hopefully will enable better diagnosis as well as staging in the coming years.

And, with the increase in number of phase III studies, we’re developing evidence-based guidelines, which will hopefully lead to more standardization, although knowing how to sequence these new drugs is still quite challenging.

OncLive: With sequencing, what are the main questions that we’re still trying to answer?

Strosberg: If we take, for example, NETs of the midgut, beyond first-line somatostatin analogs, physicians and patients often face decisions regarding where to proceed next, and for some patients with liver-dominant disease, liver-directed therapies are still an option.

For others, everolimus is a systemic option, and then hopefully lutetium dotatate will be an option based on approval of the drug, which is currently pending. Knowing how to choose among those 3 options is going to be a challenge, and I think there will be debates. Hopefully, clinical trials that compare one agent to another can help doctors make that choice. It’s even more complicated for pancreatic NETs. Beyond somatostatin analogs, we have about 5 choices—we have everolimus, sunitinib (Sutent), cytotoxic chemotherapy, liver-directed therapy, and peptide receptor radiotherapy. It’s even more challenging in that area.

OncLive: Are there any other ongoing clinical trials with some of these agents that you’re particularly excited about?

Strosberg: There’s a trial that is slated to take place in Europe which will compare lutetium dotatate with everolimus in advanced pancreatic NETs, and I think that’s going to be a very important trial that will help us get some information on both sequencing of these drugs, as well as the efficacy of Lutathera in the pancreatic NET population, based on well-run prospective clinical trials. I’m particularly looking forward to that trial.

OncLive: Looking to the future, what are some of the immediate challenges you hope to tackle with NETs?

Strosberg: One area of particular need is poorly differentiated neuroendocrine carcinomas. That’s a field that’s traditionally been understudied. There have been very few prospective clinical trials looking at this particular population, and we’re hoping that will change in the near future. There are a number of trials taking place looking at immunotherapy drugs. If these agents work anywhere in the neuroendocrine sphere, they are more likely to work in poorly differentiated or high-grade tumors, in my opinion, given the mutational profile of these cancers. So that’s something I’m particularly looking forward to being able to offer these patients something other than the cisplatin/etoposide combination that goes back decades, and is of short-lasting duration.

See more at: http://www.onclive.com/publications/oncology-live/2016/vol-17-no-24/expert-discusses-recent-progress-in-net-management#sthash.ypkilX2A.dpuf

Thanks for reading

Ronny

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Theranostics for Neuroendocrine Cancer – A Find and Destroy Mission

theranostics
Courtesy of Pashtoon Kasi MD on Twitter https://twitter.com/pashtoonkasi/status/1078675398601396224

Theranostics is a joining of the words therapeutics and diagnostics. You may also see it conveyed as ‘Theragnostics’ and these terms are interchangeable. The basic aim of theranotistics is to find and then destroy the ‘bad guys‘. With Neuroendocrine Cancer, finding the tumours (the bad guys) can often be a challenge – they can be small and/or difficult to find – they are sometimes expert at camouflage. Moreover, once found, they can then be difficult to treat (destroy), as they can often prove resistant to conventional cancer drugs and many are inoperable due to sheer quantity, spread and positioning. When they are found and identified, it’s also really helpful to know from the intelligence gathered, how successful the destroy (therapeutic) part of the mission might be.

The nuclear scan uses the same targetin agent as the therapy, therefore if you cancer lights up on the nuclear scan, then the therapy will find its way to the cancer and hopefully work well. That is the beauty of theranostic pairing, i.e. the use of the same agent in the diagnostics – the ability to find, estimate likely success criteria and then hopefully destroy – or at least reduce the capability of the tumours and extend life.

A great example of an approved Theranostic Pair in Neuroendocrine Cancer, is the combination of the Somatostatin Receptor based Ga68 PET scan using NETSPOT or SomaKit TOC™ (US/Europe respectively) and Peptide Receptor Radiotherapy (PRRT) using Lutathera which both target NETs expressing the same somatostatin receptor, with PRRT intended to kill tumor cells by emitting a different kind of low-energy, short-range radiation than that of the diagnostic version. As mentioned above, the Ga68 PET scan can give a reasonably indication of therapeutic success using PRRT based on measurements taken during the scan (too complex for this article).

Theranostics – a step towards personalised medicine – graphic courtesy of Advanced Accelerator Applications.

THERANOSTICS – FIND

Octreoscan vs Ga68 PET

Ga68 PET

Newer imaging agents targeting somatostatin receptors (SSTR) labelled with 68 Ga have been developed, namely, DOTATATE, DOTATOC and DOTANOC. They are collectively referred to as SSTR PET.

The full titles of the 3 types are:

68Ga-DOTA-Phe1-Tyr3-Octreotide (TOC),
68Ga-DOTA-NaI3-Octreotide (NOC),
68Ga-DOTA-Tyr3-Octreotate (TATE).

The main difference among these three tracers (DOTA-TOC, DOTA-NOC, and DOTA-TATE) is their variable affinity to SSTR subtypes. All of them can bind to SSTR2 and SSTR5, while only DOTA-NOC shows good affinity for SSTR3.

These agents have several benefits over In111-pentetreotide (Octreotide scan), including improved detection sensitivity, improved patient convenience due to the 2 hour length of the study (compared to 2 or 3 days with Octreoscan), decreased radiation dose, decreased biliary excretion due to earlier imaging after radiotracer administration, and the ability to quantify uptake. The quantification of the uptake can help decide whether a patient is suitable for PRRT. Eventually, all Octreotide scans should be replaced with SSTR PET. To confirm the advantages of SSTR PET over Octreotide scans, a study comprising 1,561 patients reported a change in tumour management occurred in over a third of patients after SSTR PET/CT even when performed after an Octreotide scan. Worth pointing out that SSTR PET is replacing the ageing Octreotide scan and not conventional imaging (CI). You can see the recommended scenarios for use of SSTR PET in this article published by the Journal of Nuclear Medicine

Ga68 PET scans have been in many locations for some time. Current excitement is focused on USA locations with Ga68 PET (NETSPOT) only recently approved (DOTATATE). Other countries/scan centres may use one of the other types of imaging agent.

Read much more about this scan in my detailed article on Ga68 PET here.

So SSTR PETs above have the ability to find and estimate likely success criteria for therapy. We are now in a position to move on to ‘THERApy’ – e.g. Peptide Receptor Radiotherapy or PRRT.

THERANOSTICS – DESTROY

click on picture to watch video

Lutathera® (note the ‘THERA’ which makes up the brand name)

Definitions:

Europe Approval: LUTATHERA®(lutetium (177Lu) Oxodotreotide) is indicated for the treatment of unresectable or metastatic, progressive, well differentiated (G1 and G2), somatostatin receptor positive gastroenteropancreatic neuroendocrine tumours (GEPNETs) in adults.

USA Approval: LUTATHERA® (lutetium Lu 177 dotatate) is indicated for the treatment of somatostatin receptor-positive gastroenteropancreatic neuroendocrine tumors (GEP-NETs), including foregut, midgut and hindgut neuroendocrine tumors in adults.

For commercial purposes, the drug may be slightly different on a regional basis. For all intents and purposes it does the same job.

As an example of how the drug is administered, please watch this short video from the European site:

Video courtesy of Advanced Accelerator Applications
Please see the following post for a summary of PRRT activity worldwide. Please note this linked article is not designed to contain a list of every single location or country available – please bear that in mind when you read it – CLICK HERE

I’m very grateful to the team at Advanced Accelerator Applications (a Novartis Company) for allowing me to use their site for graphics and videos.

In another ‘theranostic’ development, check out my article on the Satoreotide trial (Ops 201/202) from Ipsen (of Lanreotide fame) – click here to read – the trial is recruiting.

Thanks for reading

Ronny

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“You must be doing OK, you’ve not had chemotherapy”

chemo

If there’s a word which is synonymous with cancer, it’s chemotherapy.  It’s what most people have in their mind when they are talking to a cancer patient…… ‘have you had chemotherapy‘ or ‘when do you start chemotherapy‘.

I was nonchalantly asked by a friend some time ago ‘how did you get on with chemotherapy’ – he was surprised to hear I hadn’t had it despite my widespread disease.  Cue – lengthy explanation!  I wasn’t annoyed by the question, I just think people automatically assume every cancer patient has to undergo some form of systemic chemotherapy.  If you read any newspaper article about cancer, they do nothing to dispel that myth, as many articles contain a story about a cancer patient with no hair.

Sure, chemotherapy is not the nicest treatment to receive and it does have pretty awful side effects for most. I watched my daughter-in-law go through 3 or 4 months of this treatment where she was literally confined to a combination of her bedroom and her bathroom.  And it did shock me to see her without hair.  I would never want anyone to go through that and it really brings it home when it happens to a close member of your family.

Despite its bad press in regards toxicity and it’s awful side effects, chemotherapy is widely used in many cancers.  Statistics show that it does work for many patients (….. my daughter-in-law is still here looking after two of my four grandsons and my son still has a wife ♥).  However, I suspect it has a limited future as more efficient and less toxic drugs and delivery systems come online downstream.  Immunotherapy is often touted as a replacement for chemotherapy but this may be a while yet.  So for now, millions of cancer patients worldwide will continue to be prescribed chemotherapy as part of their treatment regime.

However, for some cancers, chemotherapy is not particularly effective. Neuroendocrine Cancer (NETs) is one such cancer. In general, NETs do not show a high degree of sensitivity to chemotherapy. For example, it’s often inadequate for the treatment of well-differentiated tumours with a low proliferation index but can be more effective in particular anatomical locations. The one exception is for high grade tumours (known as Neuroendocrine Carcinoma if poorly differentiated) where chemotherapy is much more likely to feature.  I’m not saying that the lower grades will never receive chemotherapy – that door is always left open for those with progressive cancer who perhaps have run out of treatment options.  Putting Grade 3 to one side, I’ve heard people say that NETs is the ‘good cancer or the ‘good looking’ cancer often citing the chemotherapy thing as some justification. That is of course a stupid thing to say.  I accept that not everyone will lose their hair and not every chemo will cause hair loss.

Here’s the rub.  Many other treatments come with pretty challenging side effects. Moreover, the side effects and the consequences of these other treatments can last for some time, and for many, a lifetime. For example with NETs:

Surgery can be pretty extensive, in some cases radical and life changing.  Many cancer patients receive surgery for NETs which is still the only real ‘curative’ treatment, although for most, it’s cytoreductive or palliative in nature.  If you lose bits of your small intestine, large intestine, liver, spleen, cecum and appendix, gallbladder, stomach, rectum, lungs, pancreas, thyroid, parathyroids, pituitary gland, adrenal gland, thymus gland, ovaries, oesophagus (…….I could go on), this comes with various side effects which can present some quality of life issues.  There can be huge consequences of having this treatment.

Other ‘consequences’ of cancer surgery include (but are not limited to), pulmonary emboli (blood clots), lymphedema, short bowel syndrome, gastrointestinal malabsorption, diabetes.

Somatostatin Analogues do a great job but they do add to some of the effects of surgery (mainly malabsorption).

Even the so-called ‘silver bullet’ treatment Peptide Receptor Radio Nuclide Therapy (PRRT) can have pretty severe side effects and presents some risk to kidneys and bone marrow as a long term consequence.

I’ve not had chemotherapy and I would rather avoid it if I can. However, as I’ve hinted above, there are other harsh (….perhaps harsher?) treatments out there. Moreover, whilst hair normally grows back, your small intestines, lungs and pancreas won’t.  Many people will have to live for the rest of their life with the consequences of their cancer and its treatment.

It sometimes appears that every other cancer article involves someone undergoing chemotherapy.  I just wish someone would write an article about my lack of terminal ileum and ascending colon, the malabsorption issues as a consequence of that, my missing mesenteric lymph nodes, my retroperitoneal fibrosis, not forgetting to mention my diseased liver, my left axillary lymph nodes (and the mild lymphedema I now have after their removal), my left supraclavicular lymph nodes, my suspect thyroid lesion and my hypothyroidism which may be due to that, my small lung nodule and my pulmonary emboli which after nearly 6 years of daily injections means my abdomen looks and feels like I’ve done 12 rounds with Mike Tyson.  However, it just wouldn’t be a good picture nor would it be as powerful as one of a person with no hair.  Just saying!

I look well, I still have all my hair – but you should see my insides!

insides
(you may also like this blog – click above)

I’m not playing ‘Cancer Olympics’ with this post as I wish all cancer patients, regardless of type, regardless of treatment regimes, the very best outcomes.

Thanks for reading

You may also enjoy these similar and related articles:

Things not to say to a cancer patient – click here

Shame on you! – click here

I look well but you should see my insides – click here

Things are not always how they seem – click here

Not every illness is visible – click here

Not the stereotypical picture of sick – click here

An Ode to Invisible Illness – click here

Poker Face or Cancer Card – click here

Thanks for reading

Ronny

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Remember ….. in the war on Neuroendocrine Cancer, let’s not forget to win the battle for better quality of life!

 

Neuroendocrine Cancer – Exciting Times Ahead!  

exciting-times-ahead_edited

In the last 12-24 months, there seems to have been announcement after announcement of new and/or upgraded/enhanced diagnostics and treatment types for Neuroendocrine Cancer.  Scans, radionuclide therapies, combination therapies, somatostatin analogues, biological therapies, etc.  Some of the announcements are just expansions of existing therapies having been approved in new (but significant) regions. Compared to some other cancers, even those which hit the headlines often, we appear to be doing not too badly.  However, the pressure needs to stay on, all patients need access to the best diagnostics and treatments for them; and at the requisite time.  There’s even more in the pipeline and I’m hoping to continue to bring you news of new stuff as I have been doing for the last year.

Some of these new diagnostics and treatments will benefit eligible patients who are in diagnosis/newly diagnosed and also those living with the disease. As we’re now in our awareness month, let’s recap:

Scans

Many NET Patients will undergo a nuclear scan to confirm CT results and/or to detect further neuroendocrine activity.  Basically, a nuclear substance is mixed with a somatostatin analogue, injected into the patient who is then scanned using a 360-degree gamma camera.  As gamma cameras are designed to show up radioactive activity; and as Neuroendocrine Tumour cells will bind to the somatostatin analogue, it follows that the pictures provided will show where Neuroendocrine tumours are located.  Many people will have had an ‘Octreotide’ Scan (or more formally – Somatostatin Receptor Scintigraphy) which is still the gold standard in many areas. The latest generation of nuclear scans is based on the platform of the Gallium (Ga) 68 PET Scan. The principles of how the scan works is essentially as described above except that the more efficient radioactive/peptide mix and better scan definition, means a much better picture providing more detail (see example below). It’s important to note that positive somatostatin receptors are necessary for both scans to be effective. Europe and a few other areas have been using the Ga-68 PET scans for some time (although they are still limited in availability by sparse deployment). The latest excitement surrounding this new scan is because they are currently being rolled out in USA.  Read about the US FDA approval here.  You may hear this scan being labelled as ‘NETSPOT’ in USA but this is technically the name for the preparation radiopharmaceutical kit for the scan which includes a single-dose injection of the organic peptide and the radionuclide material. Take a look at a comparison of both scans here:

octreo-vs-g68
Octreoscan output vs Gallium 68 PET output

This slide from a recent NET Research Foundation conference confirms the power of more detailed scanning.

Peptide Receptor Radionuclide Therapy (PRRT)

Similar to above, this treatment has been in use in Europe and other places for some time but is also to be formally deployed in USA if, as is expected, the US FDA approval is positive at the end of this year (Read here).  In the most basic terms, this is a treatment whereby a peptide is mixed with a radionuclide and is drip fed over a number of treatments (normally up to 4 spaced out over a year). The concept of delivery of the ‘payload’ to the tumours is actually very similar to the preparation for a radionuclide scan as described above, the key difference is the dosage and length of exposure whilst the tumours are attacked. Once again, receptors are important. The NETTER series of trials showed good results and this is an excellent addition to the portfolio for those patients who are eligible for this treatment. Fingers crossed for the US FDA announcement due by the end of this year.  Also fingers crossed that PRRT returns to the NHS England & Wales portfolio of available treatments next year.  The Carcinoid Cancer Foundation has an excellent summary of PRRT here.

PRRT and Chemo Combo

Whilst on this subject, I also want to highlight the innovative use of combo therapies in Australia where they are combining PRRT and Chemo (PRCRT).  I blogged about this here:

PRRT CAPTEM

Somatostatin Analogues and their Delivery Systems

Somatostatin analogues are a mainstay treatment for many NET Patients.  These drugs target NET cell receptors which has the effect of inhibiting release of certain hormones which are responsible for some of the ‘syndromic’ effects of the disease.  Again, receptors are important for the efficacy of this treatment.  You can read the ‘geeky’ stuff on how they work here.  These drugs mainly comprise Octreotide (provided by Novartis) and Lanreotide (provided by Ipsen). The latter has been around in Europe for 10 years and was introduced to North America earlier this year.  Octreotide has been around for much longer, almost 17 years.  When you consider these peptides have also been used to support nuclear scans that can detect the presence of tumours; and that studies have shown they also have an anti-tumour effect, they really are an important treatment for many NET Patients.  I’ve blogged about new somatostatin analogues in the pipeline and you can read this here.  This blog also contains information about new delivery systems including the use of oral capsules and nasal sprays (…….. very early days though).

Treatment for Carcinoid Syndrome

telotristat-etiprate-clinical-trial-serotonin-as-a-key-driver-of-carcinoid-syndrome

For maintenance and quality of life, the release of a Telotristat Ethyl for Carcinoid Syndrome is an exciting development as is the first new treatment for Carcinoid Syndrome in 17 years.  This is a drug which is taken orally and inhibits the secretion of serotonin which causes some of the symptoms of the syndrome including diarrhea.  It must be emphasised it’s only for treating diarrhea caused by syndrome and might not be effective for diarrhea caused by other factors including surgery.  Read about how it works and its target patient group in my blog here.

Oncolytic Virus

oncolytic

The announcement of a clinical trial for the Oncolytic Virus (an Immunotherapy treatment) specifically for Neuroendocrine Tumours is also very exciting and offers a lot of hope. Click the photo for the last progress update.  

Everolimus (Afinitor)

013490_PNETUS_iPad_pg2v2

Earlier this year, AFINITOR became the first treatment approved for progressive, non-functional NETs of lung origin, and one of very few options available for progressive, non-functional GI NET, representing a shift in the treatment paradigm for these cancers.  It’s been around for some time in trials (the RADIANT series) and is also used to treat breast and kidney cancer.  It’s manufactured by Novartis (of Octreotide fame).  It has some varying side effects but these appear to be tolerable for most and as with any cancer drug, they need to weighed against the benefits they bring.

In technical terms, AFINITOR is a type of drug known as an ‘mTOR’ inhibitor (it’s not a chemo as frequently stated on NET patient forums).  Taken in tablet form, it works by blocking the mTOR protein. In doing so, AFINITOR helps to slow blood vessels from feeding oxygen and nutrients to the tumour.

Check out Novartis Afinitor website for more detailed information.  There’s an excellent update about AFINITOR rom NET expert Dr James Yao here.  The US FDA approval can be found here.

Summary

………. and relax!   Wow, I’ve surprised myself by collating and revising the last 12-24 months.  Dr James Yao also agrees – check out his upbeat message in the attached 2 page summary.  You may also like another upbeat message from Dr Jonathan Strosberg by clicking here.

Neuroendocrine Cancer – who’d have thought it?  ….. a bit of a dark horse.

Thanks for reading

Ronny

Hey, I’m also active on Facebook.  Like my page for even more news.

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Remember ….. in the war on Neuroendocrine Cancer, let’s not forget to win the battle for better quality of life!

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Neuroendocrine Cancer: Somatostatin Receptors

ct compare to g68 pet
CT and G68 PET fused showing somatostatin receptor pick up

Don’t understand Somatostatin Receptors?  Join the club!  I got my head around the term ‘Somatostatin’ and ‘Somatostatin Analogues’ some time ago but the term ‘Somatostatin Receptor’ (SSTR) is still a bit of a mystery and it’s come to the top of my list of things to study.  SSTRs do come up in conversation quite often and I’m fed up of nodding sagely hoping it will eventually become clear! On analysis it looks like a technical subject – and therefore a challenge 🙂

I’ve taken a logical approach working from ‘Somatostatin’ to ‘Somatostatin Analogue’ before commencing on the ‘receptor’ bit.  It is intentionally brief and (hopefully) simplistic!

Somatostatin

It’s important to understand this hormone and then why your ‘butt dart’ is generically called a ‘Somatostatin Analogue’.

Some Neuroendocrine Tumours secrete hormones and peptides that cause distinct clinical syndromes, including amongst others, carcinoid syndrome.  Somatostatin is a naturally occurring hormone and a known inhibitor of some of these NET related hormones and peptides that can be over secreted and cause syndromes. For example, somatostatin from the hypothalamus inhibits the pituitary gland’s secretion of growth hormone (GH) and Thyroid Stimulating Hormone (TSH). In addition, somatostatin is produced in the pancreas and inhibits the secretion of other pancreatic hormones such as insulin and glucagon.  However, the naturally produced Somatostatin does not have the lifespan to have any effect on Neuroendocrine Tumours which are over secreting these hormones and peptides. ……. cue manufactured versions that can!

Somatostatin Analogue (SSA)

These are manufactured versions of Somatostatin known as Somatostatin Analogues.  These are designed to have a lasting effect to inhibit for much longer and therefore reduce the symptoms caused by the over secretion (i.e. the syndrome).  Examples of Somatostatin Analogue include Octreotide (Sandostatin), Lanreotide (Somatuline) and Pasireotide (Signifor).

So how do Somatostatin Analogues actually work? 

For the inhibition to work effectively, there needs to be a route into the over secreting tumours, normally via short or long acting injections or even intravenously. On the tumour cells, there are currently 5 known sub-types of ‘Somatostatin Receptors’  (SSTR) which are ‘expressed’ by most NETs.   These are known as SSTR1 through to SSTR5.  The naturally occurring hormone Somatostatin attempts to bind with all 5 but as above, it lacks the lifespan to make any impact to inhibit sufficiently in cases of overecretion. However, SSAs can overcome this with the longer lifespan.  They can successfully in most cases bind with these receptors to inhibit the hormones and peptides causing the problems, particularly SSTR2 with modest affinity to SSTR5. Clearly it’s therefore advantageous to target SSTR2.

Somatostatin Receptors

The subtypes expressed by NETs are variable and the efficiency of different SSAs in binding to each SSTR subtype also varies. For example the table below lists the variability of Somatostatin Receptor efficiency in different types of NET.  Interesting to note that non-functional NETs might not have efficient SSTRs but SSAs will still try to bind to them albeit it might not work or have a lesser effect.

Somatostatin receptors are found in high numbers on the surface of NET’s. Most receptors are in the inactive state (based on something called the phosphorylation status). Traditionally, agents such as dotatate have only bound to activated receptors on the surface.  Scientists are looking at ways to bind to inactive receptors to increase therapy success (for example see clinical trial OPS 201)

Table 1 – Somatostatin receptor subtypes in neuroendocrine tumours (mRNA) (See Copyright)

Tumour SSTR1 (%) SSTR2 (%) SSTR3 (%) SSTR4 (%) SSTR5 (%)
Gastrinoma 79a 93 36 61 93
Insulinoma 76 81 38 58 57
Non-functioning pancreatic tumour 58 88 42 48 50
Gastro-intestinal NET 76 80 43 68 77

This table above clearly shows the variability of SSTRs when binding with different types of NETs.  It follows that manufacturers of SSAs will be using this data in the formulation of their drugs.  If you now look at the table below, you can see how efficiently the 3 well-known SSAs inhibit NETs on each SSTR.

Compound SSTR1 SSTR2 SSTR3 SSTR4 SSTR5
RECEPTOR SUBTYPE AFFINITY (IC50, nM)
Octreotide 1140 0.56 34 7030 7
Lanreotide 2330 0.75 107 2100 5.2
Pasireotide 9.3 1 1.5 >100 0.16

View it in a separate window

You can see from the data why Octreotide and Lanreotide target SSTR2 and to a lesser extent SSTR5 but Pasireotide (Signifor or SOM-230) is interesting as it appears to have affinity for SSTRs 1-3 and 5, probably why it has been approved for Cushing’s Disease (ATCH producing).  However, to date, there has not been enough evidence showing that Pasireotide has a progression-free survival benefit over the other 2 therapies. It is also associated with hyperglycemia. You may find this video interesting as the doctor (Strosberg) is suggesting it could be used by NET patients in certain scenarios.

What about SSA labelled diagnostics?

The same principles apply.  For example, an Octreotide Scan (actually known as ‘Somatostatin Receptor’ Scintigraphy (SRS)) works by taking pictures using a gamma camera which is designed to see radiation from a ‘tracer’.  The tracer in question is a radio labelled with an Octreotide variant (such as pentetreotide) which will bind to somatostatin receptors on the surface of the tumour cells  In the simplest of terms, this shows up where NETs are.  The same principles apply to Ga 68 PET scans which are more advanced and more sensitive than SRS.

What about SSA labelled therapies?

With (say) Peptide Receptor Radiotherapy (PRRT), there is a similar binding mechanism going on.  In PRRT, Octreotide or a variant, is combined with a therapeutic dose of the radionuclides, e.g. Yttrium 90 (Y-90) and Lutetium 177 (Lu-177).  It binds with the SSTRs on the tumour cells and the therapeutic dose attacks the tumour having been brought there by the binding effect.  Simple isn’t it?

Do Somatostatin Receptors work for everyone?

Unfortunately not.  Some people have more sensitive receptors than others and the figure of 80% appears to be the most common statistic indicating one-fifth of all NET patients may not be able to respond correctly to SSA treatment or get the right results from Octreoscans/Ga 68 PET and/or PRRT.  However, that needs to be taken into context and probably applies to midgut NETs measured against SSTR2 – the tables above tend to confirm this figure.  During my research, I did read that higher than normal doses of SSAs may have some effect on those with less sensitive SSTRs.  Also, SSAs seem to work much better with well-differentiated tumours.

How do I know if my Somatostatin Receptors work?

When I was completing my NET checks after diagnosis, my Oncologist declared I was “Octreotide avid” shortly after my Octreoscan was compared with my CT.  I’m guessing that is a simple and crude test and how most people find out they have working receptors.  I also suspect that if your syndrome symptoms are abated somewhat by SSA injections, then you there is a good chance your SSTRs are working normally.  I also suspect those who show clear signs of tumour on CT but not on Octreoscan or Ga 68 PET, could have a receptor issue.

The advent of modern PET scanning (e.g. Ga68) has meant more accurate methods of working out if someone has the right receptors for PRRT through analysis of something known as standardized uptake values (SUV).

A more modern approach is to use a ‘Theranostic Pair” where the same radiolabelled tracer is used with the advantage that the diagnostic element can predict suitability for the therapy component  – read more here

lutathera owl - Copy


Somatostatin Receptor Research – Interest Point

I was please to see a piece of research ongoing to look at the issues with lack of somatostatin receptors.  The research is looking at novel imaging agents for NETs which do not have working receptors.  Read more here.

Summary

I hope this gives you a very basic outline of why Somatostatin Receptors are important to support the diagnosis and treatment of NETs.

My article “If you can see it, you can detect it” is almost 100% accurate but having working receptors really helps with nuclear scans.

Preclinical and clinical studies have indicated that somatostatin receptor (SSTR)expressing tumors demonstrate higher uptake of radiolabeled SSTR antagonists than of the currently approved SSTR agonist versions. See clinical trial OPS 201 for an example of the next generation of somatostatin receptor based theranostics where the use of a somatostatin antagonists.

thanks for reading

PRRT and Chemo combination therapy – on trial

 

PRRT CAPTEMI recently posted an ‘Onc Live’ video series about Neuroendocrine Tumour (NET) treatments and the final episode talked about combination treatments i.e. where more than one treatment is administered simultaneously.  An interesting and exciting area to watch for the treatment of NET patients.

Thought you’d be interested in a potential new treatment being developed in Australia.  The use of PRRT and chemo (in particular CAPTEM) or ‘PRCRT’. The attached video is a presentation by Dr Michael Hofman who I see regularly on twitter posting some very interesting stuff. He’s a great advocate for NET patients. The video will explain in some detail how the treatment is thought to work together. Additionally, it also provides excellent PRRT information. Dr Hofman has some really interesting things to say.  20 minutes – definitely recommended watching!  CLICK HERE

‘CONTROLNETS’ involving PRRT and CAPTEM. The details of the trial can be read here: CLICK HERE

 

Thanks for reading

Ronny

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PRRT and the NHS England Cancer Drugs Fund

cost cutting vs life cutting?
cost cutting vs life cutting?

As of 4 Nov 15, PRRT was delisted from the NHS England Cancer Drugs Fund. Appeals were made but were rejected, despite the glowing results from the NETTER-1 trial.  Although a replacement system is now in place, PRRT remains barred from routine NHS use.

Please see the following post for the very latest on PRRT worldwide – CLICK HERE

I was extremely disappointed to learn of the decision to remove PRRT (Lutetium or Yttrium) from the Cancer Drugs Fund (CDF) as reported by the NET Patient Foundation. You can read the detail of the decision here: CDF Statement.  PRRT has regularly been described by NET specialists and patients as the “magic bullet” due to its potential to shrink or kill tumours.

This is the second Neuroendocrine Cancer treatment to be withdrawn this year, after the earlier decision on Everolimus (Afinitor) in April . In fact, the recent cuts to the CDF were described in the media as a “massacre” as the list was reduced by two-thirds.  You can see the current CDF list by clicking here.

The timing of these cuts is extraordinary and when you look at the output from recent trial reports presented at the Europetwo-thirdsCongress (ECC) for both Neuroendocrine Cancer related drugs recently cut:

Everolimus

The RADIANT-4 trial said that Everolimus had a significant effect in non-functional NETs which are very difficult to treat.  This is particularly important for Lung NETs as no treatment currently exists.  The RADIANT-2 trial had already proven the efficacy of the drug for advanced carcinoid (in conjunction with Octreotide) and the RADIANT-3 trial proved good data for treatment with advanced functional pNETs.  Read the report here.

PRRT – 177Lu-DOTATATE

The ECC also reported a significant finding from the NETTER-1 trial.  Treatment with the novel peptide receptor radionuclide therapy (PRRT) Lutathera significantly increased progression-free survival (PFS) over Octreotide LAR (Sandostatin) in patients with advanced midgut NETs.  It shows a PFS that has never been shown before in this type of cancer adding that this was significant because these patients have a real unmet medical need.

Lutathera is a 177Lu-DOTATATE PRRT that targets somatostatin receptors, which are overexpressed in about 80% of NETs, to deliver cytotoxic radiation directly to the tumor – See more by clicking here.

To fully understand the background to the problem, you need to understand both PRRT and the Cancer Drugs Fund and a quick primer on both follows.

What is PRRT?

For those who are not entirely sure what PRRT is, here’s a quick primer from The Society of Nuclear Medicine and Molecular Imaging:

Peptide receptor radionuclide therapy (PRRT) is a molecular therapy (also called radioisotope therapy) used to treat a specific type of cancer called neuroendocrine carcinoma or NETs (neuroendocrine tumors). PRRT is also currently being investigated as a treatment for prostate and pancreatic tumors.

In PRRT, a cell-targeting protein (or peptide) called octreotide is combined with a small amount of radioactive material, or radionuclide, creating a special type of radiopharmaceutical called a radiopeptide. When injected into the patient’s bloodstream, this radiopeptide travels to and binds to neuroendocrine tumor cells, delivering a high dose of radiation to the cancer.

The cells in most neuroendocrine tumors have an abundance (called an overexpression) of a specific type of surface receptor—a protein that extends from the cell’s surface—that binds to a hormone in the body called somatostatin. Octreotide is a laboratory-made version of this hormone that binds to somatostatin receptors on neuroendocrine tumors. In PRRT, octreotide is combined with a therapeutic dose of the radionuclides. Yttrium 90 (Y-90) and Lutetium 177 (Lu-177) are the most commonly used radionuclides.  

What conditions are treated with PRRT?

PRRT may be used to treat NETs, including carcinoids, islet cell carcinoma of the pancreas, small cell carcinoma of the lung, pheochromocytoma (a rare tumor that forms in the adrenal glands), gastro-enteropancreatic (stomach, intestines and pancreas) neuroendocrine tumors, and rare thyroid cancers that are unresponsive to treatment with radioiodine.

PRRT is an option for patients:
• who have advanced and/or progressive neuroendocrine tumours
• who are not candidates for surgery
• whose symptoms do not respond to other medical therapies.

The main goals of PRRT are to provide symptom relief, to stop or slow tumor progression and to improve overall survival.

These video’s on Nuclear Medicine are by Professor Val Lewington – the UK’s most experienced person on PRRT.  I was at this presentation and she is absolutely amazing. It’s slightly dated but still very current.  This presentation also covers Octreotide and Gallium 68 scans under the heading of Nuclear Medicine – if you are still unsure about PRRT or Nuclear Medicine in general, these videos are definitely worth a watch.

The Role of Nuclear Medicine in NETs

Q&A Sessions

This is also a great source of information maintained by NET Patients in the USA.  Click here

What was the Cancer Drugs Fund?

The Cancer Drugs Fund was money the UK Government has set aside to pay for cancer drugs that haven’t been approved by the National Institute for Health and Care Excellence (NICE) and aren’t available within the NHS in England. This may be because the drugs haven’t been looked at yet. Or it may be because NICE have said that they don’t work well enough or are not cost-effective. This was introduced as a ‘political statement’ by the then Conservative/Liberal Democrat coalition government in 2010/11.  The aim of the fund is to make it easier for people to get as much treatment as possible.

The Cancer Drugs Fund was for people who live in England. The governments of Scotland, Wales and Northern Ireland decide on how they spend money on health and so far haven’t decided to have a similar programme.

Worth noting that on 1 April 2013, NHS England took on responsibility for the operational management of the Cancer Drugs Fund (CDF). The NHS spends approximately £1.3 billion annually on the provision of cancer drugs within routine commissioning. The CDF was established as an additional funding source to this.

There was a national list of drugs available through the fund – you may have heard this called the priority list. If you met the conditions for a drug that was on the list, you should have been able to have it on the NHS if you live in England. The Fund would also have considered applications on behalf of individual patients for other drugs that are not on the list.  However, under the new system, Individual funding requests (IFRs) relating to cancer drugs will no longer be considered via the CDF process.  All IFRs relating to cancer drugs will now be considered using NHS England’s single, national IFR system, which was updated in January 2016.

The new system came info force on 29 July 2016 and you can read more if you click this link

Summary

Although the decision is shocking to most, it was not totally unexpected as the Government and NHS have been hinting for sometime that the costs of the fund need to be reined in.  In any case if was only ever a temporary arrangement until a another model could be put into place.  There is a political element as the fund was set up by David Cameron with healthcare experts suggesting that it made no sense as a response to rising drug prices.  Moreover, by topping up the fund, the same experts claimed this was making the manufacturers the real beneficiaries of the fund as they have been able to sell their drugs to the NHS at prices that are unaffordable (and therefore unsustainable) for the NHS.

UK NET patients who have advanced and/or progressive neuroendocrine tumours which cannot be removed by surgery and whose symptoms do not respond to other medical therapies, still need help.

Ironically, the UK seems to be intent on cutting provision of the treatment (at least for NHS patients) as the US is trying very hard to formally introduce it.  This is a disgraceful situation and advanced Neuroendocrine Cancer patients and those who may need this treatment in the future are being terribly let down.

I will keep this blog ‘live’ in order to add information as things progress.

Thanks for reading

Ronny
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