Patients may have unrealistic expectations of phase 1 oncology trials

Nearly half of patients with cancer expected that their tumors would shrink while on a phase 1 study, although the typical response rate observed in early-phase trials ranges from 4% to 20%, according to results of a single-center, prospective, quantitative study.

Still, a majority of patients were willing to participate in phase 1 trials after they consulted the pros and cons with their physicians, results showed.

“There is a positive message in this, which is that 84% of patients are willing to participate in phase 1 oncology studies after a discussion with clinical and nursing staff who lay out the conservative estimates of benefit and requirements of hospital visits,” Udai Banerji, MD, PhD, leader of the clinical pharmacology and trials team and deputy director of the drug development unit at Cancer Research UK Cancer Therapeutics Unit of The Institute of Cancer Research in London, said in a press release. “This is good for current and future patients and cancer medicine in general.”

Phase 1 trials — designed to assess the potential of novel treatments that have not yet been tested in humans and define safe doses — typically enroll patients with advanced disease who did not respond to standard therapy. Median survival for patients on phase 1 trials is 6 months.

Banerji and colleagues sought to better understand patients’ motivations for enrolling on phase 1 trials and to quantify their expectations of the benefits, risks and commitment associated with participation.

Researchers administered questionnaires to 402 adults during their first attendance in a patient phase 1 clinic before they were seen by a clinician. A majority (n = 396; 99%; mean age, 57.4 years; 56.3% women) completed the questionnaire, and 301 patients (76%) also completed a brief follow-up version after their consultation. The most common cancers in the cohort were gastrointestinal, gynecological and lung.

Eighty-four percent of patients said the possibility of tumor shrinkage was the number-one reason why they would consider enrolling on a phase 1 trial. Other common motivations including that they had no other treatment options (56%), it was the physician’s recommendation (44.2%), the research could benefit others (38%) and family wishes (24.4%).

Researchers then assessed patients’ expectations before and after their consultation.

Originally, 42.7% of patients expected that their tumors would shrink during the phase 1 trial. After the consultation, this proportion increased to 46.8% of patients. Fourteen percent of patients expected a cure.

“The high percentage of patients expecting their tumors to shrink was a sobering finding,” Banerji said. “This creates a challenge for health care professionals to manage expectations but to do so without being patronizing or dismissing human hope.”

Further, 70.7% of patients expected moderate side effects from treatment before consultation, which increased to 77.1% of patients after consultation.

Regarding commitment, 93% of patients understood trial enrollment would require weekly hospital visits after the consultation, compared with only 49.7% prior to consultation (P < .001).

The proportion of patients who wanted to enroll on a phase 1 study increased from 71.5% prior to consultation to 84.3% after (P < .001).

Researchers acknowledged that the missing postconsultation questionnaires may have limited these findings, as patients who did not complete the questionnaires may have been determined unsuitable for phase 1 trials. Also, researchers acknowledged they did not use a questionnaire to assess patients’ anxiety or depression scores.

“We found that more than 80% of patients enrolling in early clinical oncology trials were motivated by the prospect of a clinical benefit,” Banerji and colleagues wrote. “Approximately half of patients anticipated tumor shrinkage, and approximately a tenth still expected a cure. These rates conflict with the typical phase 1 response rates of 4% to 20%, and this discrepancy demonstrates the challenges facing patients and health care professionals during their interactions in phase 1 studies.” – by Alexandra Todak

Disclosure: The researchers report no relevant financial disclosures.