Aligos says stop right now to lead hep B med after fruitless phase 1 data

Aligos went public back in October 2020, with $40 million of its overall haul going toward its hepatitis B antiviral “STOPS” medicine. But now, what’s stopping is the drug’s development.

Shares of the California biotech cratered on the news that development for ALG-010133 would end, more than halving from a prior close of $10.61 to $4.61 as of 2:20 p.m. ET Thursday.

The company decided to cease development based on emerging data from a phase 1 study called ALG-010133-101 that the therapy was not going to be effective at the highest projected dose. The company was looking to see a reduction in hepatitis B surface antigen, or HBsAg, which is a known marker for hepatitis B viral infection.

ALG-010133 is an S-antigen transport-inhibiting oligonucleotide polymer, or STOPS, molecule. The early-stage trial was being conducted in chronic hepatitis B patients.

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No dose-limiting safety issues were discovered in the trial.

Aligos’ management discussed the findings with the study review committee, and both determined the data were not sufficient to continue development of ALG-010133 and that the study should be shut down.

Chairman and CEO Lawrence Blatt, Ph.D., promised that Aligos has plenty more “clinically validated” prospects to offer in its pipeline.

Jefferies, however, noted that neither of those candidates—a capsid inhibitor and antisense oligo, both for hepatitis B—are expected to turn up any data until 2023. They also will be under pressure given there are other medicines already on the market in those drug classes.

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“Today's news comes as a surprise, though there has been some investor skepticism around the mechanism from the start,” Jefferies said in a Thursday afternoon note.

Investors could be interested in Aligos’ oral protease inhibitor for COVID-19, according to Jefferies, although that candidate is in the discovery stage, per the company's website. It could find space on the market as vaccine efficacy wains, the firm noted.

Aligos banked $150 million in an October 2020 IPO, which was to be used for the biotech's early-stage pipeline.