An evaluation of the clinical efficacy, safety, and usefulness of TE-031 in the treatment of suppurative otitis media (acute suppurative otitis media and acute exacerbation of chronic suppurative ...otitis media) was undertaken in a double-blind comparative clinical trial using Josamycin (JM) as the control drug. Patients in the TE group received 400mg/day (in two divided doses) and those in the JM group were given 1, 200mg/day (in three divided doses). The results are summarized below. 1. All patients were included in the clinical efficacy evaluations. Investigators reported efficacy rates of 64.4% and 64.8% for the TE group and the JM group respectively. The drug study committee reported clinical efficacy rates of 63.4% and 61.9% for the TE group and the JM group respectively. When the efficacy of the drugs was analyzed as a function of the type of disease, JM showed an efficacy rate superior to TE in the treatment of acute suppurative otitis media, whereas TE demonstrated greater efficacy in the treatment of acute exacerbation of chronic suppurative otitis media. However, such differences between the two treatment groups were statistically insignificant. 2. Analysis of the improvement in subjective and objective symptoms revealed no significant differences between the TE and the JM groups after 3 and 7 days of therapy. 3. Bacteriological efficacy was evaluated in terms of the eradication rates as a function of the type of disease, the type of infection, and the causative micro-organism. Such evaluations demonstrated no statistically significant differences between the two drug treatment groups. 4. With regard to the safety of the drug regimens, side effect symptoms were recorded in 9 (8.3%) of the TE group patients and in 2 (1.8%) of the JM group patients, demonstrating a higher rate of such symptoms in the TE group. Among the side-effects reported, digestive disturbances were most common, but all subsided either while drug therapy continued or was discontinued. Abnormal laboratory test values reported included an elevated GOT in one TE patient and an elevated GOT in one TE patient and an elevated GOT and GPT in two JM group patients. One JM group patient demonstrated eosinophilia. 5. Drug usefulness was analyzed for all of the patients and also as a function of the two types of suppurative otitis media under study. No statistically significant differences were found between the results in the two drug treatment groups. On the basis of the results summarized above, it was concluded that TE-031 admisistered in daily doses of 400mg is as clinically efficatious as JM administered in doses three times greater, and that TE-031 is a highly useful antibiotic for the treatment of suppurative otitis media.