ASCO: Boehringer, OSE offer promising glimpse of the immuno-oncology drug at the heart of their $1.4B deal

Boehringer Ingelheim
Boehringer Ingelheim's deal with OSE is part of the German pharma's ongoing strategy to expand its oncology portfolio. (Boehringer Ingelheim) ()

When Boehringer Ingelheim and OSE Immunotherapeutics teamed up in 2018 to develop OSE’s first-in-class checkpoint inhibitor, it was clear BI had high hopes for the immuno-oncology asset: The closely held German company paid about $18 million upfront but then piled on royalties and milestones, making the deal worth $1.4 billion to OSE.

BI and OSE unveiled preliminary data from a phase 1 trial of BI 765063 (formerly OSE-172), a SIRP-alpha inhibitor that selectively targets myeloid lineage cells, at the 2021 American Society for Clinical Oncology (ASCO) annual meeting. The researchers reported that in a phase 1 dose-escalation study in 50 patients with solid tumors, 45% of evaluable patients derived some clinical benefit from the drug.

One patient with metastatic hepatocellular carcinoma entered the trial after having undergone seven prior therapies. That patient maintained a partial response for 27 weeks and is still responding, the companies reported. Tumor samples showed increased infiltration of two types of immune cells, CD8 T-cells and macrophages, BI and OSE reported.

RELATED: OSE details novel immuno-oncology strategy targeting 'don't eat me' signaling in cancer

BI 765063  is among an emerging class of immuno-oncology drugs that target “don’t eat me” signaling, which is a strategy used by tumors to escape immune destruction. OSE’s original theory was that targeting SIRP-alpha would modulate the CD47 ligand, boosting the ability of the immune system to activate myeloid lineage cells, in turn freeing up the immune system to attack tumors.

The phase 1 trial includes patients with ovarian, colorectal, lung, breast and kidney cancers, as well as melanoma. Alexis Peyroles, CEO of OSE, said in a statement that a lack of serious side effects among patients in the trial, coupled with the early efficacy results, suggest that targeting SIRP-alpha “is a sound therapeutic strategy in solid tumors.”

CD47-targeted drugs are hot commodities in oncology these days. Last month, Arch Oncology raised $105 million to advance its anti-CD47 antibody into phase 1/2 testing. And I-MAB scored a deal with AbbVie worth up to $20 billion for an anti-CD47 antibody that recently finished a phase 1 trial.

As for BI, it has struck several deals aimed at beefing up its oncology pipeline. In January, it teamed up with Enara Bio in a deal centered around discovering novel antigens that could be the basis of new cancer immunotherapies. That deal came shortly after BI paid $1.5 billion to snap up NBE-Therapeutics, which is developing antibody drug conjugates to treat cancer.