Hepatitis B Virus Drug Development: FDA Offers Draft Guidance
With an aim to assist sponsors looking to develop hepatitis B virus (HBV) treatments, the US Food and Drug Administration (FDA) on Thursday released draft guidance covering the gamut of development stages.The guidance includes general considerations on nonclinical toxicology and virology studies, early phase clinical development, clinical pharmacology assessments, and phase 3 safety and efficacy trials.
Phase 3 trial design considerations and efficacy endpoints for the development of combination therapies for the treatment of chronic HBV infection are also discussed in the draft. In addition, development considerations for specific subpopulations, such as patients coinfected with hepatitis D virus or human immunodeficiency virus and pediatric HBV-infected patients, are also included.
Under the section on Phase 3 efficacy trial considerations, the draft features a section on other important endpoints, such as assessing progression of liver disease.
“Except for patients with advanced or decompensated cirrhosis, a statistically rigorous evaluation of endpoints of liver progression can be challenging because these events occur infrequently until late in the course of CHB [chronic hepatitis B]. However, treatment effects on these endpoints provide useful clinical information, and trials evaluating them could be used to support an expanded indication or patient population and could be summarized in appropriate sections of the label,” the draft says.
FDA also notes that the development of new HBV therapies is targeted at treatment regimens “of finite duration with low risk of virologic relapse and minimal risk of liver disease progression after the treatment is stopped.”
The draft also includes a section on considerations for antisense oligonucleotides and siRNA investigational drugs.
Other sections of the draft focus on clinical virology considerations, pharmacokinetic/pharmacodynamic considerations and labeling considerations.
Chronic Hepatitis B Virus Infection: Developing Drugs for Treatment: Draft Guidance for Industry