The surprising results of a randomized trial on patient preference for one cancer therapy over another show that patient-reported quality-of-life (QOL) differences influence treatment preference far more than physicians had imagined, suggested researchers at the 2012 Annual Meeting of the American Society of Clinical Oncology, held in Chicago, Illinois.

In a double-blind, crossover trial, 169 patients with metastatic renal cell carcinoma (mRCC) were randomized 1:1 to 10 weeks of 800 mg of pazopanib or 50 mg of sunitinib as first-line cancer treatment; after a 2-week washout period, patients received 10 weeks of the alternate treatment. The primary end point was patient preference, measured at 22 weeks.

Because patients with mRCC receive therapies for many months or even years, the team assessed whether the drug toxicity would be significant enough to make patients want to continue treatment with either drug or to switch therapy.

A total of 126 patients completed a preference questionnaire. In the primary analysis, 70% of the patients preferred pazopanib, 22% preferred sunitinib, and 8% cited no preference. After adjustments for a modest sequence effect, the difference in preference was 49% in favor of pazopanib. All other analyses showed a significant preference for pazopanib.

The most common reasons given for pazopanib preference were better QOL and less fatigue. Patients taking pazopanib had fewer dose reductions than those taking sunitinib (13% vs 20%, respectively) and fewer treatment interruptions (6% vs 12%). Adverse events were compatible with known profiles for both drugs.

The researchers, led by Bernard J. Escudier, MD, from the Institut Gustave Roussy, Villejuif, France, said that they expected patients to prefer one drug over the other because of adverse effects, but “we didn’t ever expect such a big difference between the 2 drugs.”

Physicians may perceive toxicity differences between 2 different therapies as relatively minor, but to patients, even low-grade toxicities over a long period have a significant effect on QOL, according to Escudier and colleagues. How patients feel when they take a drug over many months is not reflected in traditional reporting of adverse events.

A survey on physician therapy preferences, which was a secondary end point in this study, showed some difference in physicians' drug preferences: 61% preferred pazopanib, 22% preferred sunitinib, and 17% had no preference.

Patient-reported outcomes are increasingly being added to traditional efficacy outcomes to better understand the clinical relevance of differences in drug toxicities, Escudier and colleagues noted.

Reference

Escudier BJ, Porta C, Bono P, et al. Patient preference between pazopanib (Paz) and sunitinib (Sun): results of a randomized double-blind, placebo-controlled, crossover study in patients with metastatic renal cell carcinoma (mRCC)—PISCES study, NCT 01064310. Presented at: 2012 Annual Meeting of the American Society of Clinical Oncology; June 2012; Chicago, IL. Abstract CRA4502.