BioCryst Pharmaceuticals, Inc. announces the 48-week results from its APeX-S and APeX-2 trials and comprehensive market research which support the significant commercial opportunity for oral, once daily BCX7353 in HAE.

“The 48-week clinical trial data we now have from APeX-S and APeX-2 highlight the control patients are having over their attacks with oral, once daily BCX7353, and consequently why 75 percent of patients stayed on-study through 48 weeks when they had other choices,” said Jon Stonehouse, President and CEO of BioCryst.

“Since receiving the 24-week data from APeX-2 in May, we have conducted detailed and comprehensive market research to update our understanding of the commercial potential and value of BCX7353 with patients, treating physicians and payors. It is clear from this work that, regardless of their current treatment, HAE patients are eager to use, physicians are expecting to prescribe and payors are willing to reimburse oral once a day BCX7353,” Stonehouse added.

Key Findings from 48-week APeX-S and APeX-2 Data:

  • In APeX-2, patients experienced a rapid and sustained decrease in their attack frequency over 48 weeks. Thirty patients who were randomized to 150 mg of BCX7353 at the beginning of the study and completed 48 weeks of therapy had a baseline attack rate of 2.9 attacks per month, which declined to 1.4 attacks per month after one month and to 1.0 attacks per month at month 12.
  • APeX-2 patients who switched from placebo to 150 mg of BCX7353 at the week 24 visit saw dramatic and sustained reductions in their HAE attack rate. Their mean attack rate dropped to 0.5 attacks per month at month seven and to 0.4 attacks per month at month 12.
  • APeX-S patients taking 150 mg of BCX7353 had similar attack control as those in APeX-2. Patients completing 48 weeks of treatment on 150 mg of BCX7353 (n=73) had a median attack rate of zero attacks per month in six of the 12 months, including month 12 (week 48).
  • 75 percent of HAE patients who were on 150 mg of oral BCX7353 in the APeX-2 trial completed 48 weeks of treatment.
  • The integrated 48-week analysis across both APeX-2 and APeX-S showed no new safety findings. BCX7353 was safe and generally well tolerated in a total of 342 patients with a total of 232 patient-years of daily oral dosing. The most common adverse event was the common cold, which occurred with similar frequency in BCX7353 and placebo patients. Gastrointestinal events led to discontinuation of BCX7353 in three percent of patients. Drug-related serious adverse events occurred in three of 342 subjects (0.9%) and resolved after stopping or interrupting BCX7353 dosing.
  • In APeX-S, alanine aminotransferase levels >3xULN were seen in 14 of 49 patients who discontinued androgens within 28 days prior to study entry, compared to one of 104 patients who discontinued androgens more than 28 days prior to study entry and zero of 74 patients who had never used androgens. These observations support a proposed four-week washout period for current androgen patients before beginning therapy with BCX7353.

Key Findings from Market Research

  • The prevalence of HAE in the U.S. is higher than previously estimated. A comprehensive study of U.S. administrative claims data from 274 million covered lives establishes a prevalence of approximately 10,000 total HAE patients and 7,500 diagnosed and treated HAE patients in U.S.
  • More than 80 percent of the 100 HAE patients in the market research self-reported being on prophylactic therapy.
  • The 175 physicians in the market research, who in total treat more than 1,300 HAE patients, report they currently treat 58 percent of HAE patients with prophylactic therapy and anticipate they will treat 80 percent of HAE patients with prophylactic therapy in the future.
  • Patient demand for BCX7353 is strong, regardless of their current therapy. When 100 patients were shown the APeX-2 24-week product profile, 60 percent of HAE patients said they would be very willing to use BCX7353.
  • HAE-treating physicians expect to prescribe BCX7353 to 41 percent of their HAE patients.
  • Payors expressed a broad willingness to reimburse oral BCX7353 in pricing research with insurance plans and pharmacy benefit managers representing more than 100 million covered lives.

(Source: BioCryst)