FDA expands Pharming’s Joenja approval to younger children with APDS

Pharming Group N.V. (Nasdaq: PHAR) said September 11 that the U.S. Food and Drug Administration approved a supplemental New Drug Application expanding Joenja (leniolisib) to children aged 4 to 11 who weigh at least 27 kg and have activated phosphoinositide 3-kinase delta syndrome, or APDS. The approval covers 40 mg and 50 mg twice-daily doses. Pharming describes Joenja as the first FDA-approved treatment for that pediatric age band in the U.S.

What the FDA approved

The label expansion brings the oral treatment to younger children with the rare primary immunodeficiency, following its March 2023 U.S. approval for patients aged 12 and older. Pharming expects the newly approved doses to be available to eligible U.S. patients in October through its established specialty distribution network and patient-support infrastructure.

The weight threshold leaves a separate regulatory question open. On July 30, Pharming also submitted a separate sNDA seeking approval of lower Joenja doses for pediatric APDS patients aged 4 to 11 years who weigh 13 kg to less than 27 kg. That submission is not covered by the approval announced September 11.

Joenja is an oral, selective phosphoinositide 3-kinase delta (PI3Kδ) inhibitor. The updated U.S. indication in Pharming’s release covers APDS in adults and pediatric patients aged 4 years and older who weigh at least 27 kg. The newly approved 40 mg and 50 mg twice-daily doses extend treatment to eligible children aged 4 to 11.

How the pediatric study read out

Pharming said the approval was supported by a multinational, open-label, single-arm Phase III study in children aged 4 to 11 with APDS. Over 12 weeks, the study showed reduced lymphadenopathy and increased naïve B cells. The company described those changes as improvements in two clinically relevant hallmarks that together indicated an improvement in the underlying immune defect.

The company said the safety profile was consistent with prior Joenja experience. All treatment-emergent adverse events in the study narrative were mild to moderate, and no drug-related serious adverse events were observed.

What comes next

October is Pharming’s expected start for U.S. availability of the newly approved doses. The announcement sets out that timing; it does not establish that commercial shipments have begun. The company plans to use its existing specialty distribution and patient-support infrastructure to provide access.

For children aged 4 to 11 weighing 13 kg to less than 27 kg, the separate lower-dose sNDA remains a submission seeking approval. The September 11 announcement does not extend the approved indication to that lower-weight group.

What readers should know

APDS typically manifests in early childhood, according to Pharming’s release. Immune dysregulation and recurrent sinopulmonary infections can lead to permanent lung damage and other complications, while the disease can disrupt school and social life. The approval makes treatment available under the U.S. label earlier in childhood for patients who meet the weight requirement.

For readers following PHAR, the concrete change is an expanded U.S. indication for an existing medicine, with October availability still ahead. For families following APDS treatment, eligibility turns on both age and weight: the approval reaches children aged 4 to 11 weighing at least 27 kg, while the application for lower-weight children awaits a separate decision.

Filing path

Pharming Group N.V. furnished the FDA pediatric Joenja approval announcement in Form 6-K AccNo 0001828316-26-000037 with Exhibit 99.1 on September 11, 2026.