• BioCryst expects three regulatory approvals for berotralstat in 2020 and early 2021. These timelines remain on track.
   
  • The U.S. Food and Drug Administration (FDA) is currently reviewing a new drug application for berotralstat and has set an action date of December 3, 2020, under the Prescription Drug User Fee Act (PDUFA).
     
  • In Japan, the Pharmaceuticals and Medical Devices Agency (PMDA) is reviewing a new drug application (JNDA) for berotralstat under the Sakigake timeline, and the company expects approval in Japan in the second half of 2020.
     
  • On March 30, 2020, the company announced that the European Medicines Agency (EMA) had validated its marketing authorization application (MAA) submission for berotralstat and begun their formal review of the MAA under the centralized procedure. An opinion from the Committee for Medicinal Products for Human Use (CHMP) is expected within approximately 12 months from MAA validation.
     
• Ongoing commercial launch preparations are on track in the U.S., EU and Japan. The company does not expect delays due to COVID-19.  
   
• On May 5, 2020, the company announced that the United States Patent and Trademark Office issued a notice of allowance for a new composition of matter patent which extends patent protection for berotralstat in the U.S. market by four years through October 2039. 

• Low dose cohort (50 mg and 100 mg twice-daily) data in three treatment-naïve paroxysmal nocturnal hemoglobinuria (PNH) patients who completed 28 days of therapy shows BCX9930 inhibited complement and was safe and generally well tolerated.
   
  • Patients were severely ill with pre-treatment LDH from 3.7 to 11× the upper limit of normal (ULN) and low hemoglobin of 6.0 to 8.2 g/dL.
     
  • All patients had dose-dependent reductions in LDH and increases in hemoglobin.
     
  • No drug-related serious adverse events were observed.
     
  • No PNH patients experienced rash.
     
  • Based on the investigators' assessment of clinical benefit, all three patients continued on therapy with BCX9930 (100 mg twice-daily) following the 28-day study window.
     
• With the recent enrollment of a fourth patient with PNH, enrollment is now complete in treatment-naïve cohort 1 (50 mg and 100 mg twice-daily). Treatment-naïve cohort 2 (200 mg and 400 mg twice-daily) is expected to begin enrollment upon completion of cohort 1, with data expected in Q3 2020.
   
• The company plans to begin enrolling PNH patients resistant to C5 inhibitors in Q3 2020 and expects to report data from these treatment-resistant patients by the end of 2020.
   
• Data from the 200 mg and 400 mg twice-daily multiple ascending dose (MAD) cohorts in healthy volunteers shows >98 percent suppression of the alternative pathway beyond 12 hours and no dose-limiting adverse events. 

• Patient dosing is underway in Brazil in a randomized, double-blind, placebo-controlled clinical trial to assess the safety, clinical impact and antiviral effects of galidesivir in patients with COVID-19. The trial (NCT03891420) is being funded by the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health.
   
  • Part 1 of the trial is enrolling 24 hospitalized adults diagnosed with moderate to severe COVID-19 confirmed by PCR. Three cohorts of eight patients will be randomized to receive intravenous (IV) galidesivir (n=6) or placebo (n=2) every 12 hours for seven days. Upon completion of part 1 of the trial, an optimized dosing regimen of galidesivir will be selected for part 2 of the trial, based on part 1 results. In part 2 of the trial, up to 42 hospitalized patients with COVID-19 will be randomized 2:1 to receive IV galidesivir or placebo.
     
• In vitro testing of galidesivir against SARS-CoV-2, the virus that causes COVID-19, is underway. Galidesivir has been shown to be active against more than 20 RNA viruses in nine different families, including coronaviruses.
   
• The company also is working closely with the government to increase the supply of galidesivir.

BioCryst expects full year 2020 net operating cash use to be in the range of $125 to $150 million, and its operating expenses to be in the range of $135 to $160 million. The company's operating expense range excludes equity-based compensation expense due to the difficulty in reliably projecting this expense, as it is impacted by the volatility and price of the company's stock, as well as by the vesting of the company's outstanding performance-based stock options.

BioCryst management will host a conference call and webcast at 8:30 a.m. ET today to discuss the financial results and provide a corporate update. The live call may be accessed by dialing 877-303-8027 for domestic callers and 760-536-5165 for international callers and using conference ID # 4679821. A live webcast of the call and any slides will be available online at the investors section of the company website at www.biocryst.com. A telephone replay of the call will be available by dialing 855-859-2056 for domestic callers or 404-537-3406 for international callers and entering the conference ID # 4679821.

BioCryst Pharmaceuticals discovers novel, oral, small-molecule medicines that treat rare diseases in which significant unmet medical needs exist and an enzyme plays a key role in the biological pathway of the disease. BioCryst has several ongoing development programs including berotralstat (BCX7353), an oral treatment for hereditary angioedema, BCX9930, an oral Factor D inhibitor for the treatment of complement-mediated diseases, galidesivir, a potential treatment for COVID-19, Marburg virus disease and Yellow Fever, and BCX9250, an ALK-2 inhibitor for the treatment of fibrodysplasia ossificans progressiva. RAPIVAB^® (peramivir injection), a viral neuraminidase inhibitor for the treatment of influenza, is BioCryst's first approved product and has received regulatory approval in the U.S., Canada, Australia, Japan, Taiwan, Korea and the European Union. Post-marketing commitments for RAPIVAB are ongoing. For more information, please visit the Company's website at www.BioCryst.com.

This press release contains forward-looking statements, including statements regarding future results, performance or achievements. These statements involve known and unknown risks, uncertainties and other factors which may cause BioCryst's actual results, performance or achievements to be materially different from any future results, performances or achievements expressed or implied by the forward-looking statements. These statements reflect our current views with respect to future events and are based on assumptions and are subject to risks and uncertainties. Given these uncertainties, you should not place undue reliance on these forward-looking statements. Some of the factors that could affect the forward-looking statements contained herein include: that the ongoing COVID-19 pandemic could create challenges in all aspects of our business, including without limitation delays, stoppages, difficulties and increased expenses with respect to our and our partners' development, regulatory processes and supply chains, could negatively impact our ability to access the capital or credit markets to finance our operations, or could have the effect of heightening many of the risks described below or in the documents we file periodically with the Securities and Exchange Commission; that developing any HAE product candidate may take longer or may be more expensive than planned; that ongoing and future preclinical and clinical development of BCX9930, BCX9250 and galidesivir may not have positive results; that BioCryst may not be able to enroll the required number of subjects in planned clinical trials of product candidates; that BioCryst may not advance human clinical trials with product candidates as expected; that the FDA, EMA, PMDA or other applicable regulatory agency may require additional studies beyond the studies planned for product candidates, or may not provide regulatory clearances which may result in delay of planned clinical trials, or may impose a clinical hold with respect to such product candidates, or withhold market approval for product candidates; that actual financial results may not be consistent with expectations, including that 2020 operating expenses and cash usage may not be within management's expected ranges.  Please refer to the documents BioCryst files periodically with the Securities and Exchange Commission, specifically BioCryst's most recent Annual Report on Form 10-K, Quarterly Reports on Form 10-Q, and Current Reports on Form 8-K, all of which identify important factors that could cause the actual results to differ materially from those contained in BioCryst's projections and forward-looking statements.