Can a Zero Dollar Copay Change How Doctors Treat Acid Reflux

Heartburn is one of those complaints most people brush off. A burning feeling behind the breastbone after a big dinner, a sour taste in the throat, a restless night. For millions of Americans, though, it is not occasional. It is a chronic condition called gastroesophageal reflux disease, or GERD, and it shapes how they eat, sleep, and work.

GERD happens when stomach acid flows backward into the esophagus, the tube that carries food from the mouth to the stomach. A ring of muscle at the bottom of the esophagus normally keeps acid where it belongs. When that muscle relaxes too often or for too long, acid escapes upward. A national survey of more than 71,000 adults, published in the journal Gastroenterology, found that 30.9% had GERD symptoms in the previous week alone.

The disease comes in two main forms. Non-erosive GERD, the more common type, causes frequent heartburn, regurgitation, chest pain, or trouble swallowing without visible damage. Erosive GERD, also called erosive esophagitis, means acid has worn sores into the lining of the esophagus. When it is poorly treated, it can progress to Barrett’s esophagus and esophageal cancer. An estimated 15 million U.S. adults take a prescription drug for GERD. 

For decades, doctors have leaned on proton pump inhibitors, or PPIs, a class that includes omeprazole and esomeprazole. They are inexpensive, widely available, and effective for many people. They do not work for everyone, though. The same survey found that 54.1% of people taking a PPI daily still had persistent symptoms. That gap is the space newer medicines are trying to fill. 

Vonoprazan comes from a newer class called potassium-competitive acid blockers. Like PPIs, it targets the acid pump in the stomach lining, but it works differently. PPIs need acid to activate them and then bind to the pump permanently. Vonoprazan blocks the pump directly and reversibly, with no activation step, which delivers faster and longer-lasting acid suppression.

Phathom Pharmaceuticals, Inc. (NASDAQ: PHAT), based in Florham Park, New Jersey, sells vonoprazan in the U.S. as VOQUEZNA. The FDA first approved the tablets in November 2023. They are now cleared for erosive esophagitis and for heartburn tied to non-erosive GERD. 

Today, the company said commercially insured adults whose plans cover VOQUEZNA may pay as little as $0 per fill, but only through BlinkRx, its digital pharmacy partner. The offer covers supplies of 30, 60 or 90 days and includes free home delivery. BlinkRx also works with doctors’ offices on prior authorization, the insurer approval step that often stalls new prescriptions. Patients without coverage can pay cash starting at $55 for a 30-day supply.

There are limits. Prescriptions paid for by government programs are excluded under federal law. Massachusetts residents are also excluded, because state law bars copay help that favors one pharmacy. Eligible residents there can instead pay as little as $25 for 30 days with a savings card. 

This is not a rescue effort. Third quarter revenue reached $84.7 million, up 71% from a year earlier, on about 380,000 prescriptions. On their earnings call last week, management said prescriptions sent to BlinkRx are approved and filled at higher rates than those sent to retail pharmacies. A free copay gives doctors a reason to send more prescriptions there, and it makes the drug cost-competitive with generic PPIs for eligible patients

The obvious question is cost. Every dollar Phathom puts toward a patient’s copay reduces what it keeps from each sale, a gap the industry calls gross-to-net. Chief Financial Officer Sanjeev Narula said the impact should be insignificant and offset by additional prescriptions. That is a forecast rather than a result, and the next quarterly report will show whether added volume outweighs the deeper discount. 

The stakes are real for a company with one commercial product and a market value of roughly $490 million. GERD is common, existing treatments leave many patients unsatisfied, and Phathom now has a shorter path from prescription to doorstep. Whether that path produces steady growth depends on how many doctors are willing to change their habits.