First Medication Approved for Myelofibrosis Patients With Anemia

Patients who have myelofibrosis and anemia now have a new treatment option approved by the U.S. Food and Drug Administration (FDA): momelotinib (brand name Ojjaara).

Once-Daily Pill

On Sept. 15, the FDA approved momelotinib, a once-daily pill, for people who have MF and anemia, according to a news release from the drugmaker, GSK.

The news means patients may want to talk with their doctor about whether they should start or switch to the new medication when it becomes available by prescription, which likely will happen in a few weeks.

That advice comes from Ruben A. Mesa, MD, a hematologist and president and executive director of Atrium Health Levine Cancer Center in Winston-Salem, North Carolina, who created a video for patients and prescribers to watch after the FDA approval. Dr. Mesa was a lead investigator on the trials that led to the drug’s approval.

Momelotinib is a Janus kinase (JAK1/JAK2) and activin A receptor type 1 inhibitor that is approved for patients regardless of whether they are newly diagnosed or have taken a JAK inhibitor before.

The FDA approved momelotinib for treating intermediate or high-risk MF, including primary or secondary myelofibrosis (post-polycythemia vera and post-essential thrombocythemia), in adults who have anemia.

Pill Addresses Key Signs of the Disease

Momelotinib is now the only medication approved for both newly diagnosed myelofibrosis patients with anemia and those who have already tried treatment.

The medication addresses the key signs of the disease, including:

• Anemia

• Enlarged spleen

• Constitutional symptoms, such as fatigue, night sweats, and bone pain

MF affects about 25,000 patients in the United States, which is currently the only country in which the medication has been approved, according to the news release.

Most Patients Develop Anemia

“The vast majority of MF patients eventually develop anemia, causing them to discontinue treatments and require transfusions,” Nina Mojas, PhD, a senior vice president for GSK, said in a statement. The company notes that more than 30% of patients stop treatment due to anemia. Patients who become dependent on transfusions typically have shorter lifespans.

Approval Based Primarily on Two Trials

The FDA approval is based mainly on results from two phase 3 trials – the MOMENTUM study and the SIMPLIFY-1 trial. Both of these were multisite, randomized, double-blinded, controlled trials.

MOMENTUM compared the safety and efficacy of momelotinib with danazol. The trial met all its primary and key secondary goals. Researchers found that momelotinib was more effective than danazol in terms of reducing symptoms, reducing spleen size, and reducing the number of patients who required blood transfusions.

In the SIMPLIFY-1 trial, in patients with MF who had anemia but who had not used a JAK inhibitor before, momelotinib had about the same effectiveness as another drug, ruxolitinib, in decreasing the spleen size but not for decreasing symptoms. Momelotinib treatment was associated with fewer patients dependent on transfusions.

That’s important, Dr. Mesa said, because in addition to shorter lifespans, patients dependent on transfusions may have anxiety surrounding those transfusions, have to spend considerable time undergoing that treatment, and have worse overall quality of life.

What Are Common Side Effects of Momelotinib?

The most common side effects are thrombocytopenia (when levels of the platelets needed to stop bleeding are low), hemorrhage, bacterial infection, fatigue, dizziness, diarrhea, and nausea.

Momelotinib should not be started in patients with an active infection, and patients should be monitored for signs of infection, including reactivation of hepatitis B.

Should Patients on Another Drug Switch to This One?

If a patient has MF with anemia and is already on another drug for myelofibrosis, Dr. Mesa said, considerations for switching to momelotinib may include:

• Whether your anemia is severe,

• Whether you require transfusions

• How long you have been on other therapies

“If you’ve had a great response to the other therapies, your physician may still not recommend a change,” he said. “It is a very individualized decision.”

When Will Momelotinib Be Available?

After FDA approval, it typically takes 2-3 weeks for drug manufacturers to make the drug available by prescription, Dr. Mesa said.

“It undoubtedly will come through a specialty pharmacy and will require prior authorization from an insurance company,” he said.

Dr. Mesa explains that it’s not yet known whether insurance will cover the cost of momelotinib “although usually FDA-approved medicines are covered by most insurance companies, as well as by Medicare,” he said.

He said also with FDA approval, momelotinib likely will be added when treatment guidelines are next updated.

“Great Progress in the Field”

“We are thrilled to see momelotinib reach the clinic, giving patients and their physicians another option to help manage myelofibrosis,” said Kapila Viges, CEO of MPN (Myeloproliferative Neoplasms) Research Foundation, in a statement.

“Any new treatment that takes steps toward unlocking the mysteries of this complex and chronic blood cancer represents great progress for the field.”