PTC Therapeutics (PTCT) Update / Briefing Transcript

Summary of PTC Therapeutics (PTCT) Update / Briefing May 17, 2023 Company Overview - Company: PTC Therapeutics (PTCT) - Product: Sepiaterin - Indication: Treatment of Phenylketonuria (PKU) Key Points Industry and Product Development - Phase III Trial: The AFFINITY trial for sepiaterin in patients with fetal ketonuria has shown positive top-line results, meeting the primary endpoint of blood phenylalanine reduction [2][19] - Efficacy Results: - Overall mean blood phenylalanine reduction of 63% in the primary analysis population [2][8] - In classical PKU patients, the mean reduction was 69% [2][8] - 84% of patients achieved the target phenylalanine level of less than 360 micromoles per liter [10] - 93% of adolescents and adults met the European guideline target of below 600 micromoles per liter [10] Trial Design and Results - Trial Structure: The trial included a run-in phase where patients were treated with sepiaterin for two weeks before randomization [3][4] - Patient Population: - Total of 156 patients screened, with 103 patients showing a reduction of greater than 30% in blood phenylalanine levels [4][6] - 98 patients were randomized for the primary analysis [6] - Safety Profile: - No serious adverse events reported; common adverse events included headache and diarrhea, mostly grade one [12][13][78] - Similar rates of treatment-related adverse events between sepiaterin and placebo groups [13][78] Market Opportunity - Commercial Potential: - PKU represents a unique commercial opportunity with an estimated 58,000 patients worldwide [17] - Despite two approved therapies, a large unmet need exists, particularly for therapy-naive patients and those poorly controlled on existing treatments [17][18] - Regulatory Strategy: Plans to request pre-submission meetings with regulatory authorities and move forward with NDA and MAA submissions [19] Competitive Landscape - Comparison with Kuvan: - In a subset of patients previously treated with Kuvan, sepiaterin showed a 48% reduction in blood phenylalanine levels compared to their baseline on Kuvan [11][25] - The trial results validate the superior efficacy of sepiaterin over Kuvan, with a higher percentage of patients achieving significant benefits [25][26] Future Directions - Long-term Studies: Ongoing long-term open-label studies to assess safety and durability of sepiaterin treatment [14][19] - Phe Tolerance Protocol: Preliminary data show that patients can tolerate increased phenylalanine intake while maintaining low blood levels [16][104] Conclusion - The AFFINITY trial results position sepiaterin as a promising treatment for PKU, with strong efficacy and safety data supporting its potential to address significant unmet medical needs in the PKU patient population [19][121]