FDA approves Relypsa's drug Veltassa to treat hyperkalemia

Last Updated: 2015-10-21

By Anjali Rao Koppala

(Reuters) - The U.S. Food and Drug Administration approved Relypsa Inc's drug Veltassa (patiromer for oral suspension) to treat hyperkalemia in patients with chronic kidney disease or heart problems.

"Veltassa, a powdered medication that patients mix with water and take by mouth, works by binding potassium in the gastrointestinal tract, decreasing its absorption. In clinical trials, Veltassa was effective in lowering potassium levels in hyperkalemic participants with chronic kidney disease on at least one drug that inhibited the renin-angiotensin-aldosterone system," the FDA said in a news release.

In clinical trials, the most common adverse reactions associated with Veltassa were constipation, hypomagnesemia, diarrhea, nausea, abdominal discomfort, and flatulence.

The use of Veltassa is not appropriate for rapid correction of severe hyperkalemia because lowering of serum potassium may take hours to days, the FDA said.

Veltassa comes with a boxed warning because it binds many other orally administered drugs, which could decrease their absorption and reduce their effects. The warning recommends taking it and any other orally administered medication at least six hours apart. The drug must be dispensed with a patient Medication Guide that describes important information about its uses and risks, the FDA said.

On the approval, Relypsa's shares were up 2.1 percent in after-hours trading on Wednesday. The stock fell as much as 23 percent in regular trading ahead of the expected announcement.

Cowen and Co analyst Cristina Ghenoiu said ahead of the FDA's announcement that Veltassa could generate $1 billion in peak annual sales.

Veltassa will be able to address about 2.4 million patients in the United States who suffer from high levels of potassium, Wedbush Pacgrow Lifesciences analyst Liana Moussatos said.

Concordia Healthcare Corp's Kayexalate (sodium polystyrene), the standard-of-care treatment approved in the United States for hyperkalemia, is not considered to be effective for long-term management by doctors and physicians.

Ghenoiu said Kayexalate will soon be taken off the market due to its severe side effects, including constipation, death of intestinal cells and gastrointestinal bleeding.

Veltassa has several advantages over Kayexalate, including better binding capacity, tolerability and compliance, Moussatos said.

Relypsa entered into a two-year co-promotion agreement with Sanofi SA in August to sell Veltassa in the United States.