Phase II study of lonidamine in patients with small cell carcinoma of the lung.

Lonidamine, a substituted indazole carboxylic acid that inhibits cellular respiration, was given in an escalating oral schedule to 20 evaluable patients with measurable extensive small cell carcinoma of the lung. Two partial responses occurred. Reversible acceptable toxicity included myalgia, nausea, hyperesthesia, photophobia, somnolence, and testicular pain. The drug was not myelosuppressive. Lonidamine has modest activity in small cell lung cancer and further studies are warranted.