Factors affecting the feasibility of post-authorisation RCTs for conditionally authorised anticancer medicines: a multistakeholder perspective from a qualitative focus group study

Objective: The collection of comprehensive data from post-authorisation trials for conditionally authorised anticancer medicines is frequently delayed. This raises questions about the feasibility of post-authorisation randomised controlled trials (RCTs) that aim to address remaining uncertainties. Therefore, this study explored factors that facilitate or impede the feasibility of post-authorisation RCTs from the perspective of stakeholders directly involved in the design, medical-ethical approval, and conduct of these RCTs.

Design: We conducted four qualitative focus groups (FGs).

Setting: FG discussions focused on the oncology setting in European context.

Participants: Twenty-eight European patients, physicians, medical ethicists and pharmaceutical industry representatives participated in the FGs.

Intervention: Respondents were informed about the topic and the purpose of the FGs before and at the start of FG discussions. An FG script was used to guide the discussion, which was informed by 14 semi-structured interviews with various stakeholders.

Results: We identified factors with the potential to impact feasibility related to trial design, trial conduct, factors external to a trial and post-authorisation interaction with regulators. Factors that may be particularly relevant for the post-authorisation setting include the choice of relevant endpoints and the inclusion of a fair comparator (trial design), strategies to increase patients' and physicians' willingness to participate (trial conduct), and external factors relating to a medicine's commercial availability, the presence of competing medicines and trials and the perceptions about clinical equipoise. Post-authorisation interaction with regulators about how to obtain comprehensive data was deemed necessary in cases where a post-authorisation RCT seems infeasible.

Conclusions: Based on the identified factors, our findings suggest that patient recruitment and retention could be assessed more in-depth during regulatory feasibility assessments at the time of granting conditional marketing authorisation and that sponsors and regulators should better inform patients and physicians about the remaining uncertainties for conditionally authorised medicines and the necessity for post-authorisation RCTs. By enhancing the evaluation of trial feasibility, timely completion of post-authorisation RCTs may be facilitated to resolve the remaining uncertainties within a reasonable timeframe.