Olanzapine in the prevention and treatment of cancer-related anorexia-cachexia syndrome: interim results

Introduction. Anorexia-cachexia syndrome (ACS) and associated weight loss are common complications in cancer patients, reducing quality of life and survival. Efforts to prevent the development and correct ACS are relevant for improving treatment outcomes in preoperative chemotherapy for several malignancies. Preventing weight loss may reduce the frequency and severity of complications from chemotherapy and surgical treatment, maintain adequate dose intensity of chemotherapy, and improve patients’ quality of life. Olanzapine, an atypical antipsychotic, has demonstrated potential not only in controlling nausea but also in improving appetite in patients receiving chemotherapy.

Objective. To evaluate the efficacy and safety of prolonged low-dose olanzapine (2.5 mg/day) in preventing significant weight loss (≥5 %) in patients with localized/locally advanced gastric cancer and disseminated ovarian cancer during preoperative chemotherapy.

Materials and methods. The analysis included 30 patients. Of these, 14 were diagnosed with disseminated ovarian cancer and 16 with locally advanced gastric cancer. These tumor types were selected because the treatment plan includes a preoperative chemotherapy block followed by surgery. Preoperative treatment consisted of 3–4 cycles of systemic chemotherapy according to the nosology. A summary of patient characteristics and chemotherapy regimens is presented in Table 1. The experimental group received low-dose olanzapine (2.5 mg orally at night) daily until surgical treatment while maintaining their dietary habits. In the control group, no additional medications were prescribed, and patients adhered to their dietary habits. In both groups, nutritional support and the use of olanzapine as a component of antiemetic therapy were permitted when indicated. In the experimental group, dose escalation to the standard dose (5 mg) on days 1–4 of each chemotherapy cycle was allowed for this purpose. In the control group, olanzapine was administered at a dose of 5 mg orally on days 1–4 of each cycle as antiemetic therapy. Anthropometric parameters (height, weight, body mass index, body surface area) were assessed before the start of chemotherapy and after 3–4 cycles. Adverse events of chemotherapy were evaluated before each cycle, and surgical complications were assessed within 30 days after surgery. The primary endpoint of the study was the proportion of patients with weight loss ≤5 %. Due to the small sample size, descriptive analysis was used.

Results. Among patients who experienced weight loss during preoperative chemotherapy (n=16/30), weight loss of less than 5 % was more frequently observed in the olanzapine group – in 85 % (6 out of 7) – compared to 33 % (3 out of 9) in the control group (p>0.05). Weight stability was associated with a lower incidence of postoperative complications in the olanzapine group (13 % vs. 46.7 %) and prevented a reduction in relative dose intensity to <85 % compared to the control group (13 % vs. 26.7 %).

Conclusion. Preliminary data suggest a potential benefit of prolonged olanzapine administration at 2.5 mg/day in preventing significant nutritional deficiency and improving treatment tolerability.

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