Another competitor in the anti-CD47 race is throwing in the towel. Zai Lab has determined “due to the competitive landscape,” that internal development of monoclonal antibody ZL-1201 will be deprioritized.
Zai’s decision—disclosed in the company’s second-quarter earnings report—comes after the company had just landed on a recommended phase 2 dose in July. But as tantalizing a prospect as CD47 has been, it’s been tough sledding for pharmas trying to target it. The protein lives on the surface of cells and signals to macrophages to not break down the cell, otherwise referred to as the “don’t eat me” signal. That signal is all well and good until its weaponized by cancer cells to prevent being attacked by the immune system. The theory is that by inhibiting the signal, macrophages can gobble up problem cells. Zai’s asset was in development for multiple hematological and solid tumor types.
But across the industry, the target has proven difficult. In January, Gilead was slapped with a bevy of clinical holds on its CD47 project, magrolimab, due to an “imbalance” in adverse reactions in the treatment arm. Most of the holds were lifted a few months later, but not all.
AbbVie also undertook a couple of CD47 projects, inking a $2 billion collaboration with I-Mab in September 2020, but one of the projects has since bit the dust due to “strategic considerations.” Pfizer, on the other hand, will trudge on with the development of its anti-CD-47 asset absorbed in the acquisition of Trillium. During Pfizer’s recent second-quarter earnings call, Chief Development Officer William Pao, M.D., Ph.D. said Pfizer would “let the data speak for itself when they come in.”
Notably for Zai, ZL-1201 was one of the company’s few internal assets. The Chinese company has built much of its business around asset partnerships, offering access to the China market to foreign biotechs, which has drawn a number of valuable partners. This includes Karuna Therapuetics’ schizophrenia med KarXT and Mirati’s KRAS inhibitor, adagrasib. According to the company’s pipeline, ZL-1201 was one of six internal programs Zai was progressing.