GSK’s presence in immunology and irritation is closely centered on respiratory medicines, however the firm has expanded its attain by way of enterprise offers. The pharmaceutical large is now including meals allergy to the combination by way of its $2.2 billion acquisition of Rapt Therapeutics, a biotech firm whose lead program gives potential dosing and efficacy benefits over a blockbuster product marketed by two of GSK’s main pharmaceutical friends.

Underneath monetary phrases introduced Tuesday, GSK can pay $58 in money for every share of Rapt, representing a 65.2% premium to the inventory’s closing worth on Friday. When South San Francisco-based Rapt went public in 2019, it priced its shares at $12 every.

The Rapt drug ozureprubart is a monoclonal antibody designed to inhibit immunoglobulin E (IgE), a sort of antibody that the physique produces in massive quantities in response to an allergen. There’s already an anti-IgE antibody drug out there for folks with meals allergy symptoms, the injectable drug omalizumab each two to 4 weeks. This drug was first authorized in 2003 for the remedy of average to extreme bronchial asthma. The 2024 FDA approval of the meals allergy antibody is the most recent in a protracted line of immunological indications for the blockbuster product, marketed by companions Genentech, a subsidiary of Roche, and Novartis underneath the model identify Xolair. Roche, which information U.S. gross sales of the drug, reported 2.4 billion Swiss francs (about $3.1 billion) in Xolair income in 2024 throughout its authorized indications.

Rapt’s Ozureprubart, beforehand often known as RPT904, was developed by making focused modifications to the omalizumab sequence, extending its half-life and enhancing its drug-like properties. This long-acting antibody gives the choice of dosing each 12 weeks for prophylactic safety towards meals allergens. A part 2b trial of ozureprubart as monotherapy is underway with a focused enrollment of 100 members aged 12 to 55 years with a confirmed meals allergy. The placebo-controlled research checks eight or twelve weeks of dosing; information is anticipated subsequent yr.

In a letter to buyers, Leerink Companions analyst Thomas Smith wrote that the Rapt drug has proven best-in-class potential in IgE-mediated illnesses. That features meals allergy, an enormous business alternative for about 17 million recognized sufferers within the U.S., leaving loads of room for brand spanking new choices that ship higher efficacy and fewer frequent dosing, he stated. Smith added that the Rapt drug might supply the chance to deal with sufferers with elevated IgE ranges at baseline who should not candidates for Xolair. Leerink sees no indication-specific overlap with GSK’s immunology pipeline, lowering regulatory threat upon completion of the acquisition.

“General, we imagine the acquisition of RAPT is a powerful strategic match for GSK, which might leverage their experience in respiratory, immunology and irritation (RI&I), mixed with their broad business infrastructure, to unlock a possible multi-blockbuster alternative for ozureprubart in meals allergy and different IgE-mediated indications,” Smith wrote. “We imagine this deal was doubtless a aggressive course of with a number of bidders, however can not rule out the opportunity of aggressive bidding sooner or later.”

GSK stated the Rapt drug builds on its expertise and experience in irritation and immunology, whereas additionally tapping into the corporate’s current relationships with allergists who prescribe its respiratory medicines. GSK’s immunology pipeline has grown. Final yr, GSK paid $1.2 billion to amass Boston Prescription drugs’ ephimosfermin, a drug in growth to deal with the irritation and fibrosis brought on by the fatty liver illness often known as MASH. Enterprise offers from 2025 additionally introduced GSK drug candidates for continual obstructive pulmonary illness from startup Empirico and Hengrui Pharma. In a ready assertion, GSK Chief Scientific Officer Tony Wooden stated ozureprubart gives best-in-class potential for meals allergy.

“Meals allergy symptoms trigger severe well being penalties for sufferers with current remedy requiring injections as usually as each two weeks,” he stated. “Ozureprubart gives the chance to supply sturdy safety to sufferers by dosing each 12 weeks, and is in line with our method to amass sources that deal with validated targets and the place there’s a clear unmet medical want.”

Rapt licensed ozureprubart from a China-based biotech now often known as Shanghai Jeyou Pharmaceutical Co. That 2024 deal gave Rapt a brand new lead program after the corporate discontinued zelnecircone, an experimental remedy for bronchial asthma and atopic dermatitis. In early 2024, the FDA positioned checks of the oral small molecule on medical maintain after a report of liver failure.

The ozureprubart deal granted Rapt world rights to the drug, excluding mainland China, Hong Kong, Macau and Taiwan, the place Jeyou retains the rights. Rapt paid $35 million upfront and will pay a further $672.5 million in milestone funds, in line with firm regulatory filings. Jeyou can even obtain royalties on web gross sales of ozureprubart in relation to market. Underneath the acquisition settlement, GSK assumes duty for these funds. The Rapt pipeline additionally consists of the most cancers drug tivumecirnone, an oral small molecule CCR4 antagonist designed to forestall immunosuppressive regulatory T cells from migrating into tumors. In regulatory filings, Rapt stated it was searching for a accomplice to develop this drug.

Whereas the Rapt acquisition values ​​the biotech at about $2.2 billion, GSK estimates that its fee, minus the money Rapt has in its accounts, can be about $1.9 billion. The takeover settlement requires the vast majority of Rapt shareholders to tender their shares. GSK expects to finish the transaction within the present quarter.

Photograph by GSK