Merck to acquire Pandion Therapeutics for $1.85bn

Merck (MSD) has signed a deal to acquire Pandion Therapeutics for approximately $1.85bn, gaining access to a pipeline of immune modulators for the treatment of autoimmune diseases.

Leading Pandion’s pipeline is an engineered IL-2 mutein fused to a protein backbone – known as PT101 – that is designed to selectively activate and expand regulatory T cells (Tregs) for the potential treatment of ulcerative colitis and other autoimmune diseases.

Tregs can inhibit the activity of several different pro-inflammatory immune cell types, and are critical for self-tolerance of the immune system. The dysfunction of Tregs is associated with a number of autoimmune diseases.

The investigational candidate completed a phase 1a clinical trial earlier this year, achieving its primary objective of safety and tolerability.

In this study, PT101 expanded Tregs with a mean maximal increase up to 3.6-fold over baseline, with no evidence of expansion of natural killer T (NK) cells and pro-inflammatory conventional T (Tconv) at any dose studied.

“This acquisition builds upon Merck’s strategy to identify and secure candidates with differentiated and potentially foundational characteristics,” said Dean Li, president, Merck Research Laboratories.

“Pandion has applied its TALON technology to develop a robust pipeline of candidates designed to re-balance the immune response with potential applications across a wide array of autoimmune diseases,” he added.

Aside from PT101, Pandion’s pipeline also includes PD-1 agonists in development for a range of autoimmune diseases.

“Pandion grew out of our founders’ personal and scientific mission to change the way patients living with autoimmune diseases are treated. In just a few years, we have taken that mission from idea to clinical proof of mechanism with PT101, our lead IL-2 mutein,” said Rahul Kakkar, chief executive officer, Pandion.

“We are proud that Merck has recognised our team’s innovation and drive in creating a pipeline of diverse candidates that activate natural immune regulatory mechanisms and thereby have the potential to achieve better clinical responses for patients,” he added.

A number of other pharma companies are also developing IL-2 therapies, including Eli Lilly with a Nektar Therapeutics-partnered candidate that is currently in phase 2 trials for the treatment of systemic lupus erythematosus and ulcerative colitis.

In addition, Amgen is testing its own IL-2 candidate – AMG-592 – in patients with systemic lupus erythematosus and chronic graft-versus-host disease.