The US Food and Drug Administration (FDA) has approved Novartis’ Fabhalta (iptacopan) as the first oral monotherapy for the treatment of adults with paroxysmal nocturnal hemoglobinuria (PNH).

Fabhalta is an oral, Factor B inhibitor. It is designed to act proximally in the alternative complement pathway of the immune system.

The drug is now available for both previously treated and treatment-naïve patients.

The FDA approval is supported by the Phase 3 APPLY-PNH trial in patients with residual anaemia who earlier received anti-C5 treatment and are currently switched to Fabhalta.

It randomised 97 patients in an 8:5 ratio to either twice-daily, oral monotherapy or intravenous anti-C5 therapies.

According to the results, the Factor B inhibitor showed superiority in haemoglobin improvement in the absence of RBC transfusions and transfusion avoidance rate over patients who remained on anti-C5 therapies.

In APPLY-PNH, 82.3% of anti-C5-experienced Fabhalta patients experienced superior increases in haemoglobin levels ≥ 2 g/dL against 0% for anti-C5.

In addition, 67.7% of anti-C5-experienced Fabhalta patients showed sustained haemoglobin levels ≥ 12 g/dLa in the absence of transfusions.

The transfusion avoidance rate was found at 95.2% for anti-C5-experienced Fabhalta patients against 45.7% for anti-C5 treatment, the Swiss pharmaceutical firm said.

The approval was also based on the late-stage APPOINT-PNH trial in complement inhibitor-naïve patients.

It recruited 40 patients who received twice-daily, oral Fabhalta monotherapy.

In this trial, 77.5% of patients using the Factor B inhibitor showed increased haemoglobin levels.

Novartis US president Victor Bultó said: “The US approval of Fabhalta is an extraordinary moment for people living with PNH, their loved ones and the healthcare providers who care for them.

“This new, effective oral medicine may mean that patients can reset their expectations of living with PNH, a chronic and life-altering blood disease.

“As Novartis continues to focus on conditions with unmet patient needs, we are exploring the potential of Fabhalta in other complement-mediated diseases – with an ultimate goal to drive meaningful change for patients.”

The Factor B inhibitor is expected to be available this month in the US.