Blueprint Medicines’ Phase II PIONEER trial of Ayvakit (avapritinib) in indolent systemic mastocytosis (Ism ) is recruiting briskly, investigators and a source said. Sites are recruiting faster than expected, with few barriers to enrolment, they added.

The company announced 29 April in its 1Q21 earnings that it expects to complete enrolment of part 2 of the three-part Pioneer trial in mid-2021. A Blueprint spokesperson pointed toward company PRs when asked for comment. PIONEER is enrolling 244 patients across 31 locations in North America and Europe who fail to control at least one symptom of ISM. The trial initiated in April 2019 and has a primary completion date in May, according to ClinicalTrials.gov.

The study’s enrolment so far has been rapid, said a US-based investigator on the East Coast. The investigator’s site had recruited three patients in the part 1 dose-finding portion and is ahead of schedule for the part 2 randomised section, with six patients enrolled. Similarly, recruitment in his location is moving fast, said an investigator based in the Western US. He has enrolled 10 patients for the part 2 portion of the trial, noting this is ahead of where the centre expected to be.

In Germany, enrolment is also ahead of schedule, said a source involved. His site enlisted no patients on part 1 because of organisational issues by the ethics committee but is looking to enrol 60 patients in part 2, with recruitment attained within one month. His site has recruited five patients already, he added.

Investigators also said other sites in the US are recruiting briskly. Since more centres have become active, enrolment has been getting stronger, said the Western US source. US colleagues have found enrolment straightforward, said the East Coast investigator. Enrolment has picked up since lockdown restrictions have loosened as ISM patients tend to be Covid-19-averse because of more concerns around their health, the East Coast source added. In Germany, where centres are starting to enrol their first patients, recruitment looks to be simple as patients are well-known to physicians and eager to access the trial, said the source.

When it comes to recruitment barriers, experts noted nothing out of the ordinary, in terms of logistical and travel issues that accompany most clinical trials. There is no aspect of the inclusion or exclusion criteria that has hamstrung enrolment, said the two US investigators.

The FDA approved Ayvakit for the treatment of adults with unresectable or metastatic gastrointestinal tumours in January 2020. The drug also has a 16 June PDUFA date for systemic mastocytosis.

Sean Rai-Roche is a Healthcare Reporter for Clinical Trials Arena parent company GlobalData’s investigative journalism team. A version of this article originally appeared on the insights module of GlobalData’s Pharmaceutical Intelligence Center. To access more articles like this, visit GlobalData.