Barriers to participation in a prospective clinical trial for schwannomatosis-related pain
Scott Plotkin1, Jennifer Da1, Vanessa Merker1, Justin Jordan1, Ina Ly2, Alona Muzikansky3, michael parsons3, pamela wolters4, lei xu3, Mark Brown5, scot styren6
1Massachusetts General Hospital, 2Pappas Center for Neuro-Oncology, 3Mass General Cancer Center, 4NIH, 5Pfizer Inc., 6Pfizer
Objective:
To understand barriers to patient participation in the first therapeutic trial for schwannomatosis (SWN)
Background:
SWN is a rare neurogenetic condition characterized by severe chronic pain. A clinical trial of tanezumab, an anti-nerve growth factor antibody, was initiated for SWN-related pain (NCT04163419).
Design/Methods:
We prospectively tracked recruitment outcomes for this single-institution, phase 2, randomized, double-blind, placebo-controlled trial. Eligible subjects were ≥18 years old with moderate-to-severe SWN-related pain (11-point Numerical Rating Scale (NRS-11) score ≥5) despite treatment with alternate pain medications.
Major exclusion criteria include inability to discontinue non-steroidal anti-inflammatory drugs (NSAIDs) and diagnosis of osteoarthritis.
Results:
Enrollment began in October 2020 with a target of forty-six participants. Fifty-two subjects were screened as of March 2022, including twenty-five (48%) from the trial institution, seven (13%) from external institutions, and fifteen (29%) through the Children’s Tumor Foundation. Eight subjects enrolled as of March 2022. The most common reasons for non-enrollment included not meeting eligibility criteria (n=18, 41%), time/travel/financial burden (n=10, 23%), and pursuit of other treatment options (n=3, 7%) offering more immediate pain relief (surgery). The most common eligibility criteria which prevented subjects from participating included NRS-11 score <5 (N=6, 33%), diagnosis of osteoarthritis (N=5, 28%), and no confirmed diagnosis of SWN (N=5, 28%).
Conclusions:
We identified disease-specific, design-related, and drug-specific barriers to participation in this trial. Disease-specific barriers include the rarity of SWN and challenges confirming a SWN diagnosis. Design-related barriers include the use of a single center which amplified economic and logistical barriers of participation, requirements to discontinue NSAIDs, requirements to maintain stable dosing of other pain medications, and short duration of treatment. Lastly, drug-specific barriers included ineligibility due to diagnosis of osteoarthritis. Importantly, participants did not cite the double-blind design as a reason for non-participation. These results will inform design of future prospective clinical trials for SWN-related pain.