May 26, 2017
By Alex Keown, BioSpace.com Breaking News Staff
RESEARCH TRIANGLE PARK, N.C. – Investors are cooling off on Biocryst Pharmaceuticals (BCRX) despite the company’s strong interim reports for its Phase II hereditary angioedema (HAE) treatment. After rising about 45 percent in premarket trading, shares of Biocryst are down more than 14 percent this morning, trading at $5.74 as of 11:06 a.m.
On Thursday, the company announced results from a second interim analysis of its Phase 2 APeX-1 HAE clinical trial that pooled data from earlier trial parts. Specifically, Biocryst said patients treated with BCX7353 saw a reduction in HAE attacks in patients who received 125 mg and 350 mg dose levels compared to placebo. Additionally, the company said patients have not been affected by any serious safety concerns during the trial, although three subjects who apparently were taking the higher dose levels did discontinue use before the 28 day dosing period was complete due to gastrointestinal discomfort. The pre-specified per-protocol interim analysis included data on a total of 44 subjects with confirmed Type 1 or Type 2 HAE completing 28 days of treatment.
Jon Stonehouse, president and chief executive officer of Biocryst said in a statement that the data from this interim review supports the company’s hypothesis.
“We are delighted to see that a daily dose of 125 mg of BCX7353 results in a high level of efficacy with an improved tolerability profile compared to the 350 mg dose observed in the first interim analysis. We look forward to completing Part 3 of the trial to select appropriate doses for our pivotal program,” Stonehouse said.
BCX7353 is a novel, once-daily, selective inhibitor of plasma kallikrein currently in development for the prevention of angioedema attacks in patients diagnosed with HAE. One advantage Biocryst’s drug would have over competitors is it is oral. A final data readout from Biocryst’s Phase II trial is expected in the third quarter of this year.
HAE is a rare, genetic disorder estimated to affect about one in 10,000 to one in 50,000 people worldwide. The condition results in recurrent, localized edema (swelling). The areas of the body most commonly affected are the extremities, gastrointestinal tract, and upper airways. The swelling can be debilitating and painful, potentially impacting both work and education for people living with HAE. Swelling of the throat can be life-threatening due to asphyxiation.
While Biocryst’s Phase II data is positive, the company still has a long way to go before it attempts to carve out HAE market share dominated by the likes of Shire. Earlier this month Shire announced stellar Phase III data for lanadelumab that could potentially transform the way HAE patients are treated. The company said lanadelumab, a human monoclonal antibody designed to prevent angioedema in patients with hereditary angioedema saw “a statistically significant reduction in mean HAE attack frequency of 87 percent compared to placebo.” Additionally, Shire said whether patients were dosed biweekly or monthly, a significantly higher proportion of patients-compared to placebo-were attack free throughout the entire 26 week study period. If approved, Shire executives believe lanadelumab can generate about $2 billion in annual revenue, although some analysts have predicted the drug will only generate between $1.1 and $1.5 billion.
Shire (SHPGY) already has two HAE drugs approved by the U.S. Food and Drug Administration, Cinryze and Firazyr.