These days, drug developers are trying to do more than persuade the FDA that their products work well in patients. To increase the market appeal of their products, it also helps to compile evidence that they will save money for the health plans that approve expenditures on new drugs.
As commercial insurance companies, employers, and the government all clamor for cost-cutting measures in health care, companies such as Redwood City, CA-based Relypsa are looking past their hoped-for FDA approvals to the day when they go on the road to make sales. Relypsa is preparing to make a case that its lead drug candidate, patiromer, could help postpone the need for expensive dialysis treatments in patients with severe kidney disease, says Relypsa’s chief medical officer Lance Berman.
“If you can keep a renal patient out of the dialysis unit, you can save the payer a lot of money,” Berman says. “You also improve the quality of life of the patient.”
A decrease in dialysis costs might be an indirect benefit if patiromer accomplishes its primary purpose—to rid the body of dangerously high potassium levels in the bloodstream. If that works, it could serve as a kind of buffer, giving doctors more room to prescribe another important class of drugs that preserve kidney function but, as a side effect, raise potassium levels. It’s a complex story, but in short, Relypsa hopes to play a role in resolving a medical dilemma that often leaves doctors caught between two bad options.
Relypsa, (NASDAQ: [[ticker:RLYP]]), part of the big IPO class of 2013, has completed late-stage testing of patiromer, a polymer designed to capture excess potassium ions and transport them out of the body through the digestive tract. The buildup of high potassium levels, a condition known as hyperkalemia, can cause irregular heartbeats and even sudden death. One major cause of those high levels of potassium is chronic kidney disease, a progressive disorder that hampers the excretion of the dietary mineral.
The deterioration of kidney function can be slowed by treatment with drugs called RAAS inhibitors, which are also used to treat heart failure. These drugs can postpone the day when the patient with compromised kidney function needs dialysis. But in a medical Catch-22, the RAAS inhibitors can also cause blood potassium levels to rise. Reluctantly, doctors often suspend or reduce RAAS doses when patients develop hyperkalemia.
“The (RAAS) drugs increase hyperkalemia in patients already at risk for that,” says Relypsa CEO John Orwin.
However, if Relypsa’s drug is approved to soak up the extra potassium, doctors may be able to keep their patients on RAAS inhibitors for longer periods, the company says.
Berman says ears perked up at a meeting of health care payers when they heard of that possibility.
Chronic kidney disease is one of the serious potential consequences of Type 2 diabetes—a growing burden on the health care system. Last year, the American Diabetes Association estimated that the total costs due to diagnosed diabetes rose 41 percent in the five years between 2007 and 2012, from $174 billion to $245 billion. In 2012, $176 billion of that expense was attributed to direct medical costs. Hospital inpatient care took up 43 percent of that total medical cost.
Drug developers able to demonstrate that a new product can prevent hospitalizations or other expenses may be able to justify premium prices, or gain favorable placement in health plan formularies for the new drug.
Hyperkalemia has a range of causes, which include widespread burns, significant muscle damage, and certain blood disorders. But a major cause is kidney disease, which can result not only from Type 2 diabetes but also from high blood pressure, Berman says. Relypsa plans to seek FDA approval of patiromer as a treatment for hyperkalemia, whatever the cause.
But many patients in its target market suffer from compromised kidney function, heart failure, or both. Many are taking RAAS inhibitors, Berman says, and the potential market for patiromer also includes patients who have had to stop taking the RAAS inhibitors they need because their potassium levels are too high.
There are options for treating excess blood potassium, but they’re not considered great.
Patients can go on a potassium-restricted diet, but
