- Adding to a string of clinical failures, San Diego biotech Vical announced its investigational herpes vaccine didn't meet the primary endpoint of a Phase 2 study, spurring executives to scrap the program entirely.
- CEO Vijay Samant pointed out the study's placebo comparator arm hampered the treatment effect of Vical's vaccine. "We took careful measures to recruit patients with self-reported history of 4 to 9 recurrences annually. Despite that, the annualized recurrence rate during the trial in the placebo group was far less than what was expected based on their self-reported history," he said in a June 11 statement.
- Vical shares were down as much as 31% Monday, trading below $1.20 apiece. The company's stock has fallen 50% in the last year, and is well off its five-year high of $45.10 per share.
In his statement, Sumant said one of the priorities moving forward will be progressing a preclinical hepatitis B treatment created with Vical's proprietary DNA and lipid-delivering technologies. Yet those technologies — or, at least, how the company is using them — haven't prompted much optimism from investors, particularly as of late.
ASP0113, for instance, was a vaccine for cytomegalovirus vaccine (CMV) made via Vical's plasmid DNA delivery platform. The vaccine failed a Phase 2 trial testing it in kidney transplant patients in 2016, and then missed again earlier this year in a Phase 3 trial of patients who received hematopoietic stem cell transplants.
By February, Vical and its partner Astellas had backed off further clinical work for ASP0113 . The smaller drugmaker also eliminated half of its workforce, a move it was hoping would help maintain adequate funding through 2019.
Vical reported $24.8 million in cash and cash equivalents and $35.7 million in marketable securities as of December 31.
A clinical victory would go a long way to keeping Vical afloat, at least past the next couple years. But that's been hard to come by. In this latest study to miss its goal, investigators enrolled 261 healthy adults aged 18 to 50 who were herpes simplex virus type 2 (HSV-2) seropositive. HSV-2 is a common cause of genital herpes.
Vical said an independent safety monitoring board determined the vaccine, dubbed VCL-HB01, was generally safe and well-tolerated, with no Grade 4 adverse events or serious adverse events related to vaccination seen in the study.
With VCL-HB01 shelved, Vical has its eyes on a mid-stage study of a novel antifungal agent, VL‑2397, that it licensed from Astellas.
"Our Phase 2 trial is underway, comparing VL-2397 with standard first-line treatment for invasive aspergillosis in immunocompromised adults, which would be eligible for a Limited Use Indication assuming a successful outcome of the trial," Sumant said in the June 11 statement.