Janssen, Geron to Cut Off Enrollment in Phase II Myelofibrosis Trial

Geron announced that its collaboration partner, Janssen Research & Development, plans to suspend enrollment in a high-dose arm of a Phase II myelofibrosis trial of imetelstat, a telomerase inhibitor, and plans to close the low-dose arm completely. To date, over 90 patients have been enrolled in the trial across both dosing arms.

Janssen said activity in the 4.7 mg/kg arm did not warrant further investigation, and plans to allow eligible patients to increase their dose to 9.4 mg/kg, per investigator discretion. Enrollment in 9.4 mg/kg arm will be suspended while the trial continues, in order to obtain additional data, including a longer follow-up of 24 weeks. The safety profile was consistent with previous imetelstat clinical trials in hematologic myeloid malignancies, according to Geron, and no new safety signals were identified.

Janssen plans to conduct an additional internal data review in the second quarter of 2017. According to Geron, potential outcomes could include resuming enrollment in the 9.4 mg/kg dosing arm, with or without changes to the dosing regimen; adding a new dosing arm; or closing the trial.