How has Eiger BioPharmaceuticals developed its pipeline around its rare disease focus?

Our work began with the hepatitis delta virus (HDV), which causes the most severe form of viral hepatitis infection and currently has no approved therapy.  We identified a specific host target called prenylation, upon which HDV relies to reproduce, which stemmed from technology licensed out of the laboratory of Prof. Jeffrey Glenn, a virologist by training and faculty member at Stanford University.  With the target identified, we licensed a drug from Schering-Plough (now Merck) – a well characterized, small molecule, oral drug called Lonafarnib.  We took this drug directly into Phase 2 studies, demonstrating proof-of-concept in patients infected with HDV, followed by a full Phase 2 program where dosing regimens for a registration study were identified.  Eiger plans to move into Phase 3 with a single, pivotal clinical trial by the end of year.  Hepatitis delta is a disease that impacts 15 million to 20 million people around the world, mostly throughout the Middle East and South East Asia, and with heavy populations in China and Mongolia.  Although HDV is designated as an orphan disease in the US and EU, globalization and heavy migration from regions of high endemnicity have led to an estimated prevalence of 100,000 and 200,000 in the US and EU, respectively.

This process of developing well-characterized drugs acting on newly identified or novel targets in rare diseases significantly reduces the time and cost of drug development.  Following the same process, we built a portfolio of novel Phase 2 clinical programs targeting rare diseases with multiple programs positioned for success by identifying a novel target in a rare disease and finding an existing drug that we were able to license and bring rapidly into the clinic.  We have now done this three times over multiple diverse rare diseases, including hepatitis delta, post-bariatric hypoglycemia, and lymphedema.  Identifying drugs has been straightforward: we look for well-characterized drugs originally developed by other companies and intended for other disease states.  Because they already have extensive clinical and pre-clinical data, we have been able to take these drugs directly into Phase 2 proof of concept studies in targeted orphan diseases.

How great is the unmet need across Eiger’s areas of focus?

We are targeting rare diseases with relative large market potentials.  Hepatitis delta impacts an estimated 100,000 patients in the United States and almost 200,000 patients in Western Europe.  Post-bariatric hypoglycemia has a current estimated prevalence of around 70,000 in the United States and Europe and is growing.  With obesity and type 2 diabetes growing worldwide, so has the need for bariatric surgery and the prevalence of associated postprandial hypoglycemia which occurs in 5-10% of gastric bypass surgeries.  Lymphedema comprises two very different patient types.  Primary lymphedema impacts ~35,000 patients worldwide and is idiopathic.  Secondary lymphedema can occur in patients post-surgery or post-radiation if they have had lymphatic manipulation due to cancer, which afflicts tens of millions of people around the world.  There are no currently approved pharmacological therapies to any of our pipeline programs.

How extensive are Eiger’s in-house capabilities?

Our FTE count is currently below 20, which would be unusual even for a company with only one program in the clinic.  We have an incredible leadership team at Eiger that heavily leverage consultants and CROs, managing both exceedingly well so that we can efficiently execute on clinical development across multiple clinical programs. In parallel, we have good relationships with investigators and key opinion leaders across all of our therapeutic areas.  These key opinion leaders collectively manage the majority of patients that are currently followed.  We are able to work closely with investigators to conduct clinical trials efficiently and generate sufficient data to move the programs forward.

What are the next milestones for the candidates in the pipeline?

We just had a face-to-face meeting with the FDA on our lead program in hepatitis delta which was very positive.  The agency indicated that our next study can be a single pivotal trial for registration.  We plan to be in Phase 3 by the end of 2018, stepping from mid-stage into late-stage clinical development.  We also have three Phase 2 studies ongoing in HDV (LIMT), post-bariatric hypoglycemia (PREVENT) and lymphedema (ULTRA) – we will have top-line results from each in the third quarter of 2018.  We have several near-term catalysts for value creation.

With inherently small addressable patient populations, are there sufficient incentives to develop orphan drugs?

There are great incentives to develop orphan drugs, including increased regulatory guidance and reduced total patient population requirements in most cases.  The pricing that companies are able to obtain, especially in the United States and even in Western Europe, can be attractive.  Given that orphan populations by definition are small, they make up a small percentage of patients within a particular payer group.  Eiger is somewhat unique in that the patient populations in our targeted pipeline programs are rather large for orphan diseases.

Going forward, how will Eiger continue to broaden its orphan disease focus?

Our goal in time is to bring in additional programs to continue building the pipeline and growing our portfolio across other orphan diseases.  Having a diverse pipeline gives us multiple shots on goal – we are not limited to a specific platform and therapeutic area.

We plan to reach a successful end of Phase 2 outcome across each of our programs, and then consider options which may include strategic partnerships not only for non-dilutive funding, but to help us maximize each opportunity across the world.  Proof of success in our existing pipeline programs will allow us to bring life changing medicines to patients and become commercially successful, creating confidence in the investment community and facilitating ongoing efforts to expand the pipeline in the future by allowing us to repeat this efficient venture model.