Clinical Efficacy and Safety of Octreotide (SMS201-995) in Terminally Ill Japanese Cancer Patients with Malignant Bowel Obstruction

In patients with advanced cancer, malignant bowel obstruction (MBO) causes gastrointestinal symptoms such as nausea and vomiting leading to severely impaired oral food intake. Thus, MBO markedly diminishes the quality of life (QOL) of these patients because placement of a nasogastric tube becomes necessary. Many studies have shown that octreotide (SMS201–995; SMS), a synthetic analog of somatostatin, is effective for controlling the symptoms of MBO. This study was conducted to assess the efficacy and safety of 300-µg/day initial dose of SMS in Japanese patients with MBO and to investigate the clinical benefit of patients achieved by the improvement of nausea/vomiting based on subjective assessment. The subjects were patients with MBO that was refractory to other medical treatment and who had suffered at least two vomiting episodes per day for two consecutive days or had required a nasogastric tube. After enrollment, patients received SMS (300 µg/day) subcutaneously as a continuous injection for 6 days. Patients who responded to this 6-day course of treatment continued to receive the drug. Among 25 patients who were enrolled, 11 (44.0%) responded to treatment with resolution or improvement of nausea/vomiting. Their symptomatic improvement was assessed by quantitatively measuring the level of control of nausea/vomiting and by using a self-administered QOL questionnaire that evaluated the frequency and severity of nausea/vomiting, the proportion of patients enjoying recreational activities and the overall patient satisfaction with the therapy. SMS was well tolerated, and nausea and agitation were the only adverse events potentially related to this drug. The results of the study confirmed that the 300-µg/day dose of SMS is safe and effective for patients with MBO uncontrolled by other therapies and suggested that the relief of symptoms with nausea/vomiting by SMS could contribute to improvement of the QOL of patients.