After disclosing revised clinical results for its AFM24/atezolizumab combination treatment in non-small cell lung cancer, Affimed N.V. (AFMD, Financials) shares dropped 32% to $1.44 on Tuesday. Although the outcomes revealed minimal clinical efficacy in highly pretreated individuals, investor response points to questions over the relevance of the findings or the economic possibilities of the treatment.

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With tumor reduction seen in 48% of the 33 patients studied, the combination treatment had an overall response rate of 21% in the EGFR wild-type group. Median progression-free survival was 5.6 months; the disease control rate was 76%.

With an ORR of 24% and a DCR of 71% among 17 patients, the EGFR mutant group did somewhat better. Five patients were still on therapy for more than ten months, therefore median PFS also measured 5.6 months.

Higher AFM24 exposure patients had better results, according to a post-hoc exposure-response study containing an ORR of 46% and PFS of 7.4 months. Based on pharmacokinetic modeling, Affimed declared intentions to go with a larger weekly dosage of 720 mg.

Notwithstanding these results, the sharp drop in share price points to doubts about the therapy's ability to fill in non-small cell lung cancer treatment gaps or worries about more general clinical and commercial issues.

With its headquarters in Mannheim, Germany, Affimed emphasizes therapy using the natural immune system to attack hematologic and solid cancers. The firm will have a webcast going over the most recent findings.