3 Biotechs Leading the Pack in The Hepatitis B Space
April 14, 2017
By Mark Terry, BioSpace.com Breaking News Staff
Much more is heard of and written about hepatitis C than hepatitis B. The hepatitis C (HCV) market is dominated by Gilead Sciences with its drugs Harvoni and Sovaldi. HCV is most commonly spread through contact with infected blood. Hepatitis B, according to the U.S. Centers for Disease Control and Prevention (CDC), is also spread by blood-to-blood contact or by sexual contact. In the U.S., hepatitis B affects between 850,000 and 2.2 million people.
Samuel Rae, writing for Seeking Alpha, looks at three companies with potential near-term catalysts in the hepatitis B space—other than Gilead, which still dominates hepatitis B as well as C.
1. Dynavax Technologies Corporation
Located in Berkeley, Calif., Dynavax Technologies Corporation has HBsAg-1018, a gepatitis B vaccine. The U.S. Food and Drug Administration (FDA)’s Vaccines and Related Biological Products Advisory Committee (VRBPAC) will review the vaccine, HEPLISAV-B, on July 28 and has a PDUFA date of August 10, 2017.
The company’s vaccine has had a troubled history. Most vaccines use what is called the S antigen and an adjuvant, generally aluminum, that amplifies the immune response. Dynavax keeps the S Antigen, but uses 1018 ISS as an adjuvant. It seems to work better than aluminum, but there are safety concerns.
Rae writes, “The adjuvant used is, perhaps, so powerful that it can induce the onset of rare autoimmune diseases in patients. There are additional cardiovascular concerns.”
Although not a given, Rae thinks the FDA will approve because Dynavax has a strong and very large dataset to present and there aren’t many alternatives.
Dynavax is currently trading for $5.60.
2. ContraVir Pharmaceuticals
Headquartered in Edison, NJ, ContraVir Pharmaceuticals has two antiviral candidates for hepatitis B, TXL in a Phase IIa trial, and CRV431. CRV431 is about to enter IND-enabling studies based on preclinical data. These are not vaccines, but treatments.
The market leader is Gilead ’s Viread. TXL is a reformulation of Viread, which Rae writes, “allow(s) for the utilization of polymerase, which (or so the company hypothesizes) should result in increased bioavailability, and by proxy, reduced systemic exposure (through a reduction in circulating active compound).” That should mean reduced toxicity … hopefully.
TXL is in a Phase II dose escalation trial of 40 patients across four cohorts. Rae notes that ContraVir has been making the rounds on the conference circuit, drumming up awareness, and it’s likely there will be data released soon. “Safety is the primary on the study,” he writes, “but there’s an antiviral activity co-primary, and a number of secondaries should serve up some insight into whether the drug can actually outperform Viread, and if so, can it do so without bringing about some of the toxicity issues associated with the latter.”
ContraVir is currently trading for $1.53.
3. VBI Vaccines
Based in Portland, Ore., VBI Vaccines has a marketed product, Sci-B-Vac, a hepatitis B vaccine that mimics all three viral surface antigens of the hepatitis B virus. It’s approved in Israel and 14 other countries. It isn’t yet approved in the U.S., Europe or Canada.
Sci-B-Vac is dubbed a “third-generation vaccine.” Rae writes, “VBI has figured out a way to use mammalian cells to encapsulate the antigens that vaccines present to the immune system (as opposed to yeast cells), and this translates to a couple of core benefits over second generation vaccines—all rooted in immunogenicity (which is just another way of saying how quick, and to what degree, the immune system responds to a vaccine).”
The company has established Phase III protocols in Europe and Canada and is trying to do the same thing with the FDA. Because there’s so much safety and efficacy data available from other approved locations, especially Israel, it seems likely that there will eventually be approval.
VBI Vaccines is currently trading for $5.11.