Merck, Pfizer won their FDA nod for fourth-to-market SGLT2 drug Steglatro. Now what?

One of the fastest-growing classes of diabetes drugs now has a new contender: Steglatro, the SGLT2 drug from Merck & Co. and Pfizer. When it rolls out in January, the drug will have to tackle the tough task of winning share from some entrenched rivals.

The FDA approved Steglatro, formerly known as ertugliflozin, late Wednesday alongside two combination versions: Steglujan, which pairs it with Merck's stalwart diabetes drug Januvia; and Segluromet, a metformin-Steglaro duo. The approval was based on a range of clinical trial data that included one head-to-head combo test against Januvia itself. 

Merck and Pfizer are counting on that data—and the Januvia combo in particular—to help them win over payers and physicians who are already familiar with the trio of SGLT2 drugs Steglaro will be competing against.

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Pricing might come into it, too: A Merck spokesperson said Thursday that the list price for Steglatro and Stegluromet will be $8.94 per day, or about $268 for a 30-day supply, while Steglujan will run at $17.45, or $523.50. But that's the sticker cost before rebate deals with payers, and given the pressures in diabetes these days, the companies might be willing to cut some deals in return for exclusive formulary placement next time those negotiations roll around.

Steglatro's rivals would be Jardiance, the Eli Lilly and Boehringer Ingelheim drug that was the first diabetes therapy to show heart benefits in a clinical trial—and to win an FDA approval to cut the risk of cardiovascular complications. Then there's Invokana, the first-to-market SGLT2 med that brought in $1.27 billion for Johnson & Johnson last year. And AstraZeneca's Farxiga, which isn't as strong in the U.S. as it is in some European countries where it dominates the SGLT2 field.

But Merck and Pfizer are working on their case, and the Steglujan combo is part of it. Januvia is far and away the leading DPP-4 med, and Merck has every incentive to keep Januvia competitive as prescription trends shift. Earlier this year, the ertugliflozin suite put up some data that adds to the tandem's case: In a frontline study,patients taking the lowest Steglatro dose (5 mg) alongside Januvia saw their A1C levels come down by 1.6%. Patients in the placebo arm, by contrast, saw just a 0.4% decline.

RELATED: Merck, Pfizer amp up ertugliflozin outcomes study as SGLT2 med scores in PhIII

“We think ertugliflozin, both as a single component, but, in particular, in combination with sitagliptin, really has quite a compelling efficacy and safety profile,” Merck Research Laboratories’ Sam Engel told FiercePharma at ADA this year. Steglatro and Steglujan are gunning for a launch in January, while Segluromet is expected to roll in February.

The lay of the land has already been changing in the SGLT2 field. Jardiance has been racking up a bigger share of new scripts since its CV approval came through, and it benefited further when the FDA slapped an amputation risk warning on Invokana. According to Evercore/ISI analysts, prescription data shows Jardiance is gaining on Invokana as the leader of the class; the Lilly-BI drug has a slightly larger share of new prescriptions now, and it's threatening to overtake Invokana in total prescription numbers.

Meanwhile, the entire class could benefit from some new real-world evidence. Presented at the American College of Cardiology meeting in March, a real-world analysis sponsored by AstraZeneca showed that SGLT2 meds could dramatically cut down on heart failure hospitalizations and deaths, and a follow-up analysis presented at the American Diabetes Association's annual meeting confirmed it. AZ’s execs suggested at the time that the data make a case for using SGLT2s earlier in treatment—and that would add even more potential patients to the pool.