Pfizer to acquire Trillium Therapeutics

Pfizer and Trillium Therapeutics yesterday announced that the companies have entered into a definitive agreement under which Pfizer will acquire Trillium, a clinical-stage immuno-oncology company developing innovative therapies for the treatment of cancer. Under the terms of the agreement, Pfizer will acquire all outstanding shares of Trillium not already owned by Pfizer for an implied equity value of $2.26 billion, or $18.50 per share, in cash. This represents a 118 per cent premium to the 60-day weighted average price for Trillium.

Trillium’s portfolio includes biologics that are designed to enhance the ability of patients’ innate immune system to detect and destroy cancer cells. Its two lead molecules, TTI-622 and TTI-621, block the signal-regulatory protein α (SIRPα)–CD47 axis, which is emerging as a key immune checkpoint in hematological malignancies. TTI-622 and TTI-621 are novel and potentially best-in-class SIRPα-Fc fusion proteins that are currently in phase Ib/II development across several indications, with a focus on hematological malignancies, Pfizer said in a statement.

“The announcement reinforces our commitment to pursue scientific breakthroughs with the addition of potentially best-in-class molecules to our innovative pipeline,” said Andy Schmeltz, Global President and General Manager, Pfizer Oncology.

He also said, “The proposed acquisition of Trillium builds on our strong track record of leadership in oncology, enhancing our hematology portfolio as we strive to improve outcomes for people living with blood cancers around the globe. Our deep experience in understanding the science of blood cancers, along with the diverse knowledge base we have developed across our growing hematology portfolio of eight approved and investigational therapies, provide us with a foundation to advance these important potential medicines to patients who need them.”

The statement also mentioned that hematological malignancies are cancers that affect the blood, bone marrow and lymph nodes. This classification includes various types of leukemia, multiple myeloma and lymphoma. More than one million people worldwide were diagnosed with blood cancer in 2020, representing almost six per cent of all cancer diagnoses globally. In 2020, more than 700,000 people worldwide died from a form of blood cancer.

“We’re delighted to announce Pfizer’s proposed acquisition of Trillium. The announcement reflects Trillium’s potentially best in class SIRPα–CD47 status and contribution to immuno-oncology,” said Dr Jan Skvarka, Chief Executive Officer, Trillium.

He added, “Trillium has the only known SIRPα–CD47 targetting molecules with clinically meaningful monotherapy responses as well as a strong basis for combination therapies, which is supported by pre-clinical evidence with a diverse set of therapeutic agents. With Pfizer’s global reach and deep capabilities, we believe our programmes will advance more quickly to the patients we’ve always aspired to serve. We believe this is a good outcome for patients and our shareholders.”

The statement also said that in clinical studies till date, TTI-622 and TTI-621 have demonstrated activity as monotherapy in relapsed or refractory lymphoid malignancies, including Diffuse Large B-cell Lymphoma (DLBCL), Peripheral T-cell lymphoma (PTCL), Follicular Lymphoma (FL) and other lymphoid malignancies. As of 26th July, 2021, phase-1 data for TTI-622 in 30 response-evaluable patients have shown deep and durable responses in heavily pre-treated patients, including two complete responses (CRs), one lasting over 114 weeks, with responses ongoing.

TTI-622 and TTI-621 are currently the only known CD47-targetted molecules that have demonstrated meaningful single-agent activity and CRs in multiple hematological malignancies. Thus far, adverse events (AEs) reported with TTI-622 and TTI-621 have been manageable. Related Grade 3 and 4 AEs with TTI-622 were rare and limited to transient cytopenias. In particular, the molecules demonstrate minimal red blood cell binding and few reported cases of anemia, an observed risk with other CD47-targetted approaches. Further data are expected to be shared at a forthcoming medical conference, it also said.

“We are encouraged by the early clinical data for TTI-622 and TTI-621 monotherapy for patients with heavily pre-treated lymphoid malignancies and early encouraging activity for TTI-622 in patients with multiple myeloma. Just as PD-1 and PD-L1 blockers have proven to be effective immuno-therapeutics for many solid tumours, the SIRPα-CD47 interaction defines a second key immune checkpoint for which disrupting agents are expected to become another important backbone immunotherapy for multiple types of cancer, especially hematological cancers,” said Chris Boshoff, MD, PhD, Chief Development Officer, Oncology, Pfizer Global Product Development.