Pfenex Inc.s investigational osteoporosis drug PF708 showed an overall profile comparable with Eli Lilly and Co.'s Forteo in a phase 3 study after 24 weeks of treatment in osteoporosis patients.
PF708 is being developed as a therapeutic equivalent to Forteo, which is indicated for osteoporosis patients with a high risk of fracture. Osteoporosis is a condition that weakens bones and increases risk of bones breaking.
The study enrolled a total of 181 patients, with 90 patients receiving PF708 and 91 receiving Forteo. Among these, 82 patients completed the PF708 treatment and 81 patients completed the Forteo treatment.
The biosimilar drugmaker's study met its main goal, which was anti-drug antibody incidence after 24 weeks of drug treatment. At week 24, there were two anti-drug antibody-positive findings for PF708 compared with none for Forteo, but the difference was not statistically significant.
Secondary endpoints included mean percentage changes in lumbar-spine bone mineral density and median percentage changes in bone turnover markers after 24 weeks of drug treatment, as well as pharmacokinetic parameters for up to four hours after the first dose.
PF708 and Forteo showed comparable effects on lumbar-spine BMD, P1NP or N-terminal propeptide of type 1 procollagen, which is a marker of bone formation and CTX or cross-linked C-terminal telopeptide of type 1 collagen, which is a marker of bone resorption.
There were no statistically significant differences in any of these parameters between PF708 and Forteo.
San Diego-based Pfenex plans to submit a new drug application to the U.S. Food and Drug Administration in the third quarter of 2018.