The American Society of Clinical Oncology (ASCO) and Friends of Cancer Research have drafted five US Food and Drug Administration (FDA) guidance documents focusing on cancer clinical trial eligibility criteria for patients with brain metastases, HIV/AIDS, organ dysfunction, prior and concurrent malignancies and minimum age for enrollment.
The 30 pages worth of recommendations “aim to maximize the generalizability of clinical trial results while also maintaining the safety of clinical trial participants,” the groups wrote. “We believe that the rationale for excluding patients from eligibility for a cancer clinical trial should be clearly articulated and should be based on the specific therapy under investigation and the study population to help improve trial accrual, ensure optimal patient access, and maximize information learned during the clinical trial.”
Every year, about 70,000 patients living with cancer in the US will eventually develop brain metastases, though patients with brain metastases have frequently been excluded from clinical trials due to restrictive exclusion criteria.
“Given the high incidence of patients who present with brain metastases, the systematic exclusion of these patients from clinical trials may mean that one half to one third of intended-use disease populations are not included in the assessment of the agent’s efficacy or safety,” the draft guidance says. “Moreover, the exclusion of these patients limits the sponsor’s ability to learn about the safety and effectiveness of the agent in patients with brain metastases even though such patients are likely to receive such therapies following approval.”
The draft features different approaches for including patients with treated and/or stable brain metastases, those with active brain metastases and those with leptomeningeal metastases.
HIV, Hepatitis B, Hepatitis C
This draft guidance, while noting that exclusion of patients with HIV, HBV, or HCV infections remains common in most studies of novel cancer agents, features recommendations on evaluation of immune function and criteria related to HIV therapy, in addition to criteria for determining eligibility for those with HBV and HCV.
The draft offers recommendations for including patients with certain renal, cardiac and hepatic functions.
“Patients with organ dysfunction are often excluded from clinical trials, regardless of knowledge of the metabolic pathways and excretory routes of the agent under investigation,” the guidance notes. “The general population is aging and thus includes increasing numbers of patients with renal disease, hepatic dysfunction, and cardiac disease due to co-morbid illnesses.”
Prior or Concurrent Malignancies or Comorbidities
By excluding individuals with previous or concurrent cancers or comorbidities, the draft notes, trial recruitment often favors younger patients.
“Explicitly including patients with prior and concurrent malignancies rather than removing prior and concurrent malignancies as an exclusion may have a positive effect on accrual,” the guidance notes, offering recommendations for those with prior or concurrent malignancies and comorbidities.
This draft guidance features development and regulatory considerations for approaches for inclusion in oncology clinical trials, evidence to support the exclusion of pediatric patients in oncology clinical trials and more on the benefit and risk determination and labeling.