[Clinical application of NK 631, a new derivative of bleomycin (author's transl)]

It is impossible to accurately evaluate NK 631 as an anticancer agent from the findings only in the 7 cases; hence, the following is no more than the author's impression about the drug. However, NK 631 appeared to exert a similar anticancer effect to the currently available bleomycin. In other words, the drug will completely cure or greatly improve the early cases of squamous cell carcinoma, and bring about a transient regression in the advanced cases. The response of malignant lymphoma to this drug varied from case to case; in any event, it is impossible to anticipate a complete cure in this malignancy by single NK 631 therapy but by multiple combination chemotherapy, e.g., BEMP therapy. The adverse reactions to NK 631 that were observed included pulmonary fibrosis, though only in 1 case; hence, no conclusive opinion should be given herein about it pulmonary toxicity in comparison with the pulmonary toxicity of bleomycin. It remains a theme of the future statistic studies in a large number of cases. The other adverse reactions were anorexia and mild alopecia in some of the cases, which were similar to those to bleomycin. Pigmentation also occurred in one of the cases, but the author was impressed that this reaction was less likely to occur with NK 631.