Zai Lab takes a second punt on MediLink

Zai Lab, whose deal with MediLink has already given it one of the industry's most promising anti-DLL3 ADCs, has gone back to its partner again. The second deal, announced on Thursday with no financial terms, has more of a technology access feel, involving MediLink applying its conjugation expertise to an existing Zai Lab ADC, ZL-6201.

ZL-6201 was first disclosed last November, and has now been revealed as targeting LRRC15, a type I transmembrane protein overexpressed in mesenchymal tumours such as sarcoma, glioblastoma and melanoma. This target features only a few other industry projects, according to OncologyPipeline, AbbVie having apparently discontinued the only one to have entered clinical trials.

That AbbVie ADC was samrotamab vedotin (ABBV-085), which completed phase 1 six years ago. Zai Lab says that not only does LRRC15 promote tumour metastasis, it is also upregulated in cancer-associated fibroblasts, contributing to an immune system-suppressing tumour microenvironment.

However, samrotamab vedotin data, presented at ASCO in 2019, showed rather modest efficacy: among 85 patients there were just five partial responses. One response was in combination with gemcitabine, and four were seen among 40 sarcoma patients; all four of the latter were seen among 20 patients given 3.6mg/kg, but there were no responses at higher or lower doses.

JP Morgan

The latest MediLink tie-up, struck just before the JP Morgan healthcare conference gets under way on 13 January, is in line with Zai Lab's recent comments on ADCs and deal-making.

Speaking to ApexOnco on Tuesday, Zai Lab's chief operating officer, Josh Smiley, said: "We’ve followed [MediLink] for quite some time, we like their platform, and we’d love to do another deal with them. We’ll stay close to them, because there are other targets we’re interested in, and they’re a good company with a validated platform."

In general, Zai Lab wants to do several of these types of late-preclinical/early clinical deals per year, Smiley said. The MediLink transaction follows similar tie-ups done in recent days by Lonza's Synaffix division, which licensed its ADC technology to Boehringer Ingelheim, an existing partner, and to Mitsubishi Tanabe Pharma.

Despite these early deals pre-JP Morgan news has so far been worryingly negative, with several companies, including CytomX, I-Mab and Repare, announcing portfolio cuts and cost reductions. This suggests that several biotechs think their chances of raising additional cash in the near term are limited.

Industry projects targeting LRRC15

Source: OncologyPipeline.