Phase II study of high-dose fish oil capsules for patients with cancer-related cachexia

The authors undertook a multiinstitutional Phase II cooperative group study to examine the potential of oral fish oil fatty acid supplements administered at high doses to slow weight loss and to improve quality of life in patients with malignancy-related cachexia.

Patients with advanced malignancy and weight loss > or = 2% of body weight in the preceding month took concentrated, high-dose omega-3 fatty acid capsules (7.5 g eicosapentaenoic acid plus docosahexaenoic acid for a 70 kg individual) that were supplied by the National Institutes of Health.

Forty-three patients with moderate or severe malnutrition were enrolled. The median time receiving treatment was 1.2 months. For the 36 patients who took at least 1 capsule and did not have edema, there was a weight change ranging from -6.2 kg to +3.5 kg and an overall median weight loss of 0.8 kg. Twenty-four patients had weight stabilization (a gain of < or = 5% or a loss of < 5%), 6 patients gained > 5% of their body weight, and 6 patients lost > or = 5% of their body weight. There was marked variability in the tolerability of the capsules, and many patients had gastrointestinal side effects. There was a correlation between time receiving treatment and weight gain for the 22 patients who were able to tolerate the capsules for at least 1 month. Quality-of-life scores were superior for patients who gained weight.

A majority of patients did not gain weight, and in that sense, the results of the study were unfavorable. However, a small but definite subset of patients had weight stabilization or weight gain. This suggests that omega-3 fatty acids have potential utility at the study doses, which were more than twice the doses used in published Phase III studies.