Merck Secures FDA Approval for New Version of Cancer Drug Keytruda

Merck has received US approval for Keytruda Qlex, a new formulation of its cancer drug Keytruda that can be administered as a simple shot under the skin in 2 minutes, compared to the original intravenous infusion lasting 30 minutes. The new version works equally well and reduces the total time required for patients and caregivers by half. Merck expects 40% of current Keytruda patients to switch to the new version over the next two years, as the original's patents are set to expire in 2028 and face government price negotiation starting in 2029.

Merck & Co. has received US approval for Keytruda Qlex, a novel formulation of its blockbuster cancer drug Keytruda. The new version can be administered as a simple shot under the skin in about two minutes, compared to the original intravenous infusion lasting 30 minutes. Keytruda Qlex maintains the same efficacy as the original while cutting the total time required for patients and caregivers by half.

The approval comes at a critical juncture for Merck. Keytruda, expected to bring in more than $30 billion this year, is nearing patent expiration. Its key patents are set to expire in 2028, opening the door for generic rivals that could cost 50% less. Additionally, the drug is expected to face government price negotiation starting in 2029, compounding the pressure on Merck's biggest source of revenue. The launch of Keytruda Qlex provides Merck with a strategic advantage, with new patents and no imminent threat of negotiation, to fight the original's inevitable decline.

Merck expects about 40% of current Keytruda patients to switch to the new version over the next two years. The company has not yet disclosed the price for Keytruda Qlex, but the intravenous version has a list price of about $200,000 per year.

The shift to subcutaneous (SC) delivery of PD-1/PD-L1 inhibitors is a significant milestone in the evolution of immunotherapy. Merck's Marjorie Green, MD, senior vice president and head of oncology clinical development, predicts that the new formulation will "build on this breakthrough medicine to give patients and those who treat them better experiences." The FDA is expected to approve a SC version of pembrolizumab (Keytruda) by this fall, further solidifying Merck's position in the market.

However, the adoption of SC formulations will hinge on drug pricing and overall value. Experts caution that the cost of making a change, including inventory management, updating treatment plans, and educating staff, must be weighed against the benefits of clinic time saved and potential home infusion access for patients. The specter of biosimilars arriving in 2028 is top of mind for both Merck and BMS, and the pricing of SC versions will be crucial in retaining market share.

The first SC formulations have already launched in the US, with Genentech's atezolizumab and hyaluronidase-tqjs (Tecentriq Hybreza) approved for SC injection in September 2024. BMS' SC nivolumab reached the market in the first quarter of 2025, and Merck's SC pembrolizumab is expected to launch in October 2025.

The biggest selling point of SC formulations is the reduced delivery time, from 30 minutes to 5 minutes or less. Pharmaceutical sponsors claim that this shift can free up space in cancer clinics and double the time between treatments. Clinical trials have shown that patients and physicians find SC formulations to be a home run, with high preference rates and adherence.

In conclusion, Merck's approval of Keytruda Qlex is a strategic move to combat the challenges posed by patent expiration and biosimilars. The new formulation offers a more convenient dosing schedule for patients and caregivers, potentially improving patient outcomes and clinic efficiency. However, the success of this move will depend on the pricing and overall value proposition of the new version.