Pfizer is building up its pipeline of experimental cancer medicines, announcing Monday a deal to buy the Cambridge, Massachusetts-based biotech Trillium Therapeutics for nearly $2.3 billion.
The acquisition marks a dramatic turnaround for Trillium, which was worth less than $50 million at the start of last year. Under deal terms, Pfizer agreed to pay $18.50 per share of the biotech, valuing the company at a premium of more than 200% to the stock's closing price on Friday.
By buying Trillium, Pfizer gains access to two drugs in early stages of clinical testing for a range of blood cancers, like lymphoma, as well as certain solid tumors. Both therapies are designed to work by blocking signaling between specific proteins on cancer and immune cells that are thought to prevent the body's defenses from attacking tumors.
Interrupting this cellular messaging, Trillium hypothesizes, could unleash the immune system against cancerous cells, much in the same way that drugs like Merck & Co's Keytruda and Roche's Tecentriq work by blocking the proteins PD-1 and PD-L1.
"Just as PD-1 and PD-L1 blockers have proven to be effective immuno-therapeutics for many solid tumors, 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, head of cancer drug development at Pfizer, in a statement. (CD47 refers to the protein that's overexpressed on certain cancer cells, while the signal-regulatory protein α, or SIRPα, is a receptor on myeloid cells.)
A number of other drugmakers are also going after CD47 with experimental cancer treatments, most notably the California biotech Forty Seven, which Gilead bought last year for $4.9 billion. AbbVie and Boehringer Ingelheim have each struck licensing deals for drugs developed by China's I-Mab and French biotech OSE Immunotherapeutics.
Others, such as Bristol Myers Squibb, Innovent Biologics and Zai Lab, have compounds in early development.
Blood cancers appear the focus for Pfizer and Trillium, which, prior to Monday's buyout, had advanced two drugs into Phase 1b/2 testing across several tumor types. Initial data showed treatment led to responses, including two complete remissions, among 30 patients. Detailed data will be presented at future medical conferences, the companies said.
Pfizer and Trillium envision using the drugs in combination with other therapies, too.
For Pfizer, the deal extends a yearslong effort to strengthen the company's cancer drug business, a push that's mirrored the broader pharmaceutical industry's focus on oncology over the past decade. Since 2015, seven Pfizer drugs have been approved to treat breast and lung tumors as well as leukemia — including the company's top-selling cancer medicine, Ibrance.
The $2.3 billion paid for Trillium is particularly rich: Since 2018, only two other biotech deals have featured a higher premium than the 204% implied by Pfizer's offer of $18.50 per share, according to data from BioPharma Dive.
Trillium was already familiar to Pfizer, which late last year invested $25 million in the company's stock and installed one of its executives on Trillium's scientific advisory board.
The acquisition is subject to approval by two-thirds of Trillium's shareholders.