Long-term Safety and Efficacy Study and Dose-Escalation Substudy of PF 06838435 in Individuals With Hemophilia B

Summary

Long-term safety and efficacy follow-up for participants with Hemophilia B who were previously treated in the C0371005 (formerly SPK-9001-101) study, and a dose-escalation sub-study evaluating safety, tolerability, and kinetics of a higher dose with long-term safety and efficacy follow-up. Participants in the substudy do not need to have participated in C0371005.

Timeline

Start

2017-06-22

Primary completion

2029-05-29

Completion

2029-10-25

Publications

• Samelson-Jones BJ, Rasko JEJ, Ducore JM, McGuinn CE, George LA, von Mackensen S, Borgonuovo G, Agathon D, Smith L, Wilcox LJ, Biondo F, Plonski F. Safety, efficacy, and patient-reported outcomes 6 years after fidanacogene elaparvovec in adults with hemophilia B. Blood Adv. 2026 May 26;10(10):3517-3526. doi: 10.1182/bloodadvances.2025019174.
• Wojciechowski J, Gaitonde P, Hughes JH, Ravva P. Population Modeling of Factor IX Activity Following Administration of Fidanacogene Elaparvovec Gene Therapy in Participants with Hemophilia B. Clin Pharmacokinet. 2025 Oct;64(10):1531-1548. doi: 10.1007/s40262-025-01535-y. Epub 2025 Aug 1.
• Rasko JEJ, Samelson-Jones BJ, George LA, Giermasz A, Ducore JM, Teitel JM, McGuinn CE, High KA, de Jong YP, Chhabra A, O'Brien A, Smith LM, Winburn I, Rupon J. Fidanacogene Elaparvovec for Hemophilia B - A Multiyear Follow-up Study. N Engl J Med. 2025 Apr 17;392(15):1508-1517. doi: 10.1056/NEJMoa2307159.

Drugs

Indications