This is an investigator-initiated, exploratory, multicenter, open-label, single-arm clinical trial and a substudy of the Platform Research for Innovative Medicines in NF2-SWN (PRIME-NF2). The study aims to evaluate the safety, tolerability, and preliminary efficacy of luvometinib in combination with serplulimab in patients with NF2-related schwannomatosis (NF2-SWN) with progressive tumors.

NF2-related schwannomatosis (NF2-SWN) is a rare autosomal dominant disorder characterized by multiple central nervous system tumors, most commonly vestibular schwannomas and meningiomas. Although current treatments such as surgery and radiotherapy can provide disease control, they are not curative and are associated with cumulative neurological morbidity and potential risk of secondary malignancies. There remains a significant unmet need for effective systemic therapies.

This investigator-initiated study is conducted as a substudy within the Platform Research for Innovative Medicines in NF2-SWN (PRIME-NF2). The trial evaluates luvometinib in combination with serplulimab in patients with progressive NF2-SWN.

Luvometinib (FCN-159) is a selective MEK1/2 inhibitor with antitumor activity in NF1-associated tumors. Serplulimab (HLX10) is an anti-PD-1 monoclonal antibody approved for multiple solid tumors. Preclinical evidence suggests that MEK inhibition may enhance tumor immunogenicity and synergize with immune checkpoint blockade.

The study aims to assess the safety, tolerability, and preliminary efficacy of this combination in NF2-SWN.

Inclusion Criteria:

1. Participants must meet the diagnostic criteria for NF2-SWN.
2. Presence of at least one measurable target tumor, either vestibular schwannoma or meningioma, with MRI-documented volumetric progression within the past 36 months or clinical symptom progression related to the target tumor.
3. The target tumor is considered unsuitable for surgery because of high risk.
4. Age >=18 years at the time of screening.
5. KPS >=70 or ECOG performance status 0 or 1.
6. Adequate organ function based on laboratory tests obtained within 14 days before screening.
7. Participant must be able to understand the study and voluntarily sign informed consent.

Exclusion Criteria:

1. Pregnant, planning to become pregnant, or currently breastfeeding.
2. Participation in another interventional clinical trial within the past 4 weeks, or radiation therapy to target lesion(s) within the past 3 years.
3. Severe adverse reactions or intolerable toxicity from prior immune checkpoint inhibitors or MEK inhibitors.
4. Concomitant active malignancies, uncontrolled infections, or active autoimmune diseases.
5. Severe cardiac, hepatic, renal, gastrointestinal, or ophthalmic diseases.
6. Any other factor that may compromise participant safety or study integrity.