TS2023

Focus Group 2
The needs and challenges developing long-acting treatments for hepatitis C

 

Ashwin Balagopal: Rapporteur 

Co-chairs: Meg Doherty & Jordan Feld

A single-shot HCV cure is desired and would address those left behind, even if not for all patients – progress since LEAP 2022. 

  • Estimates of dosing requirements.
  • LONGEVITY project (Andrew Owen) – progress with glecapravir co-formulation.
  • Broad consideration of use cases of LA agents (CID supplement 2022).
  • Understanding patient preferences.
    • Survey by Weld ED and Thomas DL (CID 2022): pills (51%) injection (38%); implant (6%); GRD (6%).
    • UNITAID/Sue Swindells – study to better understand patient/provider preferences.
  • Some understanding of best current candidates vs newer agents.
  • Public-private partnership will be required – opportunity for funding agencies.

Industry perspective. Considerations involve all aspects of drug development. 

  • Minimal monitoring approach pioneered by the ACTG is encouraging for POC cure.  
  • Viral kinetics – how to deliver two drugs to establish SVR (VS <LLOD for 28-30d days after undetectable levels achieved)
    • Sofosbuvir considered – unique PK properties make this challenging.
    • Combination oral and injectable – resistance may develop if 8-12 weeks required.
    • If 2 agents required (NS5A inhibitor and NS3 inhibitor), can expect DDIs.
  • What is the unmet need given the success of oral antivirals?
  • What would the reimbursement be?
  • What reduction in SVR is acceptable?
  • The pathway to development and approval might not be short, and there are legal aspects.
  • Product development would be for bioequivalence – need to show non-inferiority vs standard oral therapy? need for P1 studies in healthy volunteers?

Questions and comments posed to Industry.

  • There is an unmet global need if all populations are considered – there may be more itinerant populations than have been estimated (e.g., persons in prison are often a use case for efficacy of oral therapies, but many are not there for the full duration of treatment due to turnover).
  • LA treatment is one necessary, complementary arm of an elimination strategy.
  • What are the bottlenecks before industry advances on LA medicines?
    • No rapid POC test exists for effective implementation of POC HCV cure.
    • Some pharma questions exist that cannot be solved in isolation.
      • Who pays? What are the regulatory benchmarks? How technically feasible is co-formulation?

Real-world experience with development of LA HIV treatment.  

  • CAB LA and RPV LA approval was slow – the “who pays?” question slowed progress.
  • Unmet need may be similar to HIV – people who engage with LA HIV treatment really like it.
  • Real-world surveys suggest equipoise –more people may take 1-2 shots if offered.
  • LA treatments are being rolled out in LMICs.
  • Timeline for HIV LA medicines.
    • P1 CAB/RPV studies presented at CROI 2012 (4-5 years of pre-clinical work) and approval in 2021.
    • LEN was faster – once the pipeline is built, there may be downstream advantages.
  • What gaps can academia and industry fill together?
    • Quantify unmet need; What will be accomplished by delivery of these products?; POC HCV test; Modeling.

How mathematical modeling can help. (Dr. Hoelek from Imperial College)

  • Models can show impact.
  • Consider incorporating the care cascade.
    • If the care cascade is leaky (i.e., the unmet need), then quantify the leakiness and how the opportunity you are offering will affect the leakiness.
    • Certain populations are more vulnerable to leakiness – likely geographically heterogeneous.
  • Consider the overall cost of the product (every country values the opportunity and costs differently).
  • What is the case for investment?
    • Individual gain? Societal gain? Benefits regarding transmission?
  • It is cost-saving for payers to treat HCV.

Advocacy perspective. 

  • What will it take for funders to become interested in LA HCV treatment?
  • How can we address transmission and treatment as prevention?
    • The care cascade is missing people, even with government buy-in.
  • A rapid HCV test exists (1.5 hours) – roll out or optimization to make POC cure possible?
  • Potentially a very important market – could be studied and characterized better.

Regulatory/FDA perspective.  

  • Oral adherence and tolerability is high – may be hard to get buy-in with an inferior SVR.
  • Would pan-genotypic treatment be a requirement for a LA agent?
  • What is the comparator – registrational trials or real-world experience?
  • LA therapy will inherently give higher exposures (more safety data) or lower exposures (more efficacy data).
    • Original trials include duration-finding, but not much dose-finding – toxicity of higher doses?
  • Non-inferiority trials are not always required, but there may be questions for lower SVR.
  • Interested in working with academia, industry, and pharma to identify the right studies.
    • Proposed P3 “intent-to-cure” study (randomization at diagnosis to LA vs standard oral treatment) – the SVR would reflect real-world experience, accounting for theoretical loss of efficacy.

Other thoughts.

  • Is there a role for intensification for shorter duration?
  • What types of co-formulations would be optimal?
  • Manufacturing needs its own discussion – not touched on.
  • Other formulations are important and were not fully discussed (i.e., aqua suspension; capsules; polymer-based products; injectables).

Summary thoughts.

  • What are the individual and societal benefits?
  • What is the unmet need?
  • What is the investment case?
  • What formulations would work?
  • What will payers accept?
  • What testing is required for POC cure?
  • Perfect opportunity for funders to facilitate P-P partnerships.
     

It’s about getting everyone around the table to agree to do the right thing.” Dr Doherty

This could be the opportunity for one and done.” Dr Weld

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