Enanta pins $73M IPO bid on a hot hep C blockbuster contender

Watertown, MA-based Enanta Pharmaceuticals is about to find out if one of the hottest products in late-stage development for hepatitis C can excite investors about its $73 million IPO. The biotech has priced 4 million shares at $14 to $16 apiece, betting that its big role in a closely-watched hepatitis C study will provide enough cash to fund the developer for some time to come. And underwriters have the option of picking up 600,000 shares.

Enanta has a pipeline of products, but its ABT-450, a crucial piece of AbbVie's Phase III hep C program, that it's resting the bulk of its hopes on. In the spring of 2012 Enanta and Abbott ($ABT) announced that the protease inhibitor--developed by the two companies in a collaboration--along with ribavirin and ABT-072 in an interferon-free combo delivered a sustained viral response at 24 weeks after 12 weeks of treatment for 91% of genotype 1 patients. And 82% of patients achieved SVR 36.

That data helped Enanta win recognition as a 2012 Fierce 15 company.

AbbVie's big rival in the hep C race is Gilead ($GILD), which is already on its way to the FDA with late-stage data from a slate of studies. But analysts expect several cocktails will eventually share a growing multibillion dollar market. And AbbVie has been committing a big share of its R&D resources to come in close behind Gilead. In the S-1, Enanta estimates that an NDA for the program should be ready in about two years.

That ambition has paid off for Enanta, which says it has rounded up an impressive $189 million in partnership cash and venture funds, according to its amended S-1. Then there's $430 million in potential development milestones from AbbVie and Novartis--partnered on an NS5A inhibitor--plus $240 million for approvals and sales milestones and a tiered royalty deal.

In a common ploy, Enanta's insiders have pledged to buy close to 1.5 million shares, or about 38% of the total. Its shares will be traded as $ENTA.

Biotech IPOs have had mixed results in recent months, but with the market up to record highs after years of seeing little or no traction in the public markets, a number of drug developers have been lining up to file IPOs. Tetraphase, another Massachusetts Fierce 15 company, is also going public this week.

- here's Enanta's S-1

Special Reports: Enanta Pharmaceuticals – 2012 Fierce 15 | Top 10 biotech IPOs of 2012