PTK7 seems key for Kelun

Kelun this week marking SKB518 as a “key product” in its R&D pipeline might raise some eyebrows. Very little is known about this antibody-drug conjugate, which only entered its first human trial just over a month ago, or its precise mechanism of action. However, close analysis of the study’s entry on the Chinese clinical trials registry reveals prior treatment with a PTK7-targeted drug as an exclusion criterion, so on this basis it’s safe to assume that SKB518 hits PTK7. Interestingly, the same study’s entry on the clinicaltrials.gov registry makes no mention of this exclusion criterion. Activity at PTK7 (protein tyrosine kinase 7) is a relatively uncommon mechanism, and OncologyPipeline reveals just one other clinical-stage ADC – PRO1107, originated by ProfoundBio and now owned by Genmab. In June Day One paid MabCare $55m for rights to the preclinical MTX-13/DAY301, while last year AbbVie discontinued the Pfizer-partnered cofetuzumab pelidotin. Kelun is perhaps best known for being Merck & Co’s partner for certain ADC assets, two of which the US firm returned last October. It’s not known whether SKB518 might have been one of these, but at present the asset is marked as wholly owned in Kelun’s pipeline.

ADCs targeting PTK7

Source: OncologyPipeline.