To evaluate the long-term efficacy and safety of galcanezumab in preventing migraine, an international team of researchers conducted an open-label extension of the phase 3 PERSIST trial. Their findings revealed that the drug was effective and well tolerated, and the full trial results were published in The Journal of Headache and Pain.
The 3-month, open-label extension trial enrolled 484 patients from multiple study sites in China, India, and Russia. Almost all (99.4%) of those who completed the 3-month, double-blind part of the PERSIST trial entered the trial. Those who received galcanezumab during PERSIST continued to receive it in a dose of 120 mg monthly at all 3 monthly visits of the open-label extension. Those who received placebo during PERSIST received an initial, 240 mg loading dose of galcanezumab, then 2 monthly 120 mg doses of the drug. The open-label extension study’s primary outcome measure was the mean change from double-blind baseline in the number of monthly migraine headache days (MHDs) by month 6. Secondary outcome measures were reduction in monthly MHDs from double-blind baseline to month 6, functional outcomes, safety, and tolerability.
The full 6 months of the study were completed by 96% of patients. Patients who continued to receive galcanezumab, 120 mg monthly, had a continued reduction from baseline in the mean number of monthly MHDs, which slightly increased from 4 days at the end of the double blind period to 4.6 days at the end of the extension, and 66% of patients who had a response to galcanezumab of at least 50% at month 3 maintained this response to month 6. Patients in the group that received placebo during PERSIST had a rapid reduction in the number of monthly MHDs after they began to receive galcanezumab. In this group, the mean reduction in MHDs from baseline to month 6 was 4.6 days.
“The long-term benefits of galcanezumab were also supported by improvements in other efficacy and functional endpoints,” the study report authors wrote. “All safety findings were consistent with the known long-term safety profile of galcanezumab; no patients experienced a treatment-related serious adverse event.”
These findings prompted the study report authors to conclude that “Galcanezumab was efficacious and well-tolerated in patients with episodic migraine from China, India
and Russia, for up to 6 months.”
Limitations of this study were the absence of a comparator arm or blinding, which limits the interpretability of the results obtained during the open-label period, and the brevity of the study, which leaves the longer-term safety and efficacy of galcanezumab undetermined in these patients.
Disclosure: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.
Zhou J, Zhong L, Chowdhury D, et al. Galcanezumab in patients with episodic migraine: results from the open-label period of the phase 3 PERSIST study. J Headache Pain. 2023;24:103. doi:10.1186/s10194-023-01613-1