A Study of Obexelimab in Patients With Relapsing Multiple Sclerosis (MoonStone)

Zenas BioPharma

Status and phase: Enrolling; Phase 2

Conditions: Relapsing Multiple Sclerosis

Treatments: Drug: Placebo; Drug: Obexelimab

Study type: Interventional

Funder types: Industry

Identifiers

NCT06564311

ZB012-02-002

Details and patient eligibility

About

This study aims to examine the efficacy and safety of obexelimab in participants with relapsing multiple sclerosis

Full description

The study consists of a Screening Period (Day -28 to Day -1), a 24-week treatment period (Part A and Part B), and an expected 12-week Follow-up Period. Patients with Relapsing Multiple Sclerosis will be randomized in 2:1 ratio to obexelimab or placebo. Randomization will be stratified by Gd lesion status at screening (≥ 1 vs 0).

Part A is the 12-week Randomized Placebo-Controlled Period (RCP), during which obexelimab or placebo will be administered as weekly subcutaneous (SC) injections. Following Part A, all patients will enter the Part B, Open-Label Period (OLP), during which all patients will receive obexelimab administered as weekly SC injections. Patients will return for an in-clinic Safety Follow-Up Visit 12 weeks after the completion of Part B (i.e. Week 36). If at this time, B cells have not returned to baseline or above the lower limit of normal (LLN), patients will be asked to return every 12 weeks until B cells return to baseline or above the LLN (at minimum). The maximum expected duration of the study is 40 weeks (Screening Period = 4 weeks, Parts A and B = 24 weeks, Follow-up Period = 12 weeks).

Enrollment: 93 estimated patients

Sex: All

Ages: 18 to 60 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

1. Diagnosis of RMS (relapsing-remitting or secondary progressive with relapses) according to the 2017 revision of the McDonald diagnostic criteria

2. An EDSS of ≤ 5.5 at the Screening Visit

3. Must have documentation of:

   1. . at least 1 relapse within the previous year OR
   2. . ≥ 2 relapses within the past 2 years OR
   3. . ≥ 1 active Gd-enhancing brain lesion on an MRI scan within the past 6 months prior to screening

4. Not of childbearing potential or willing to follow contraceptive guidance

Exclusion criteria

1. Primary progressive MS or secondary progressive MS without relapses
2. Meet criteria for neuromyelitis optica spectrum disorder
3. Relapse in the 30 days prior to randomization
4. ≥ 10 years disease duration from onset with patient's EDSS ≤ 2.0 (patient reported is adequate in absence of written medical record)
5. Has > 20 Gd+ lesions on brain MRI at screening

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Quadruple Blind

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93 participants in 2 patient groups, including a placebo group

Obexelimab

Experimental group

Description:

Obexelimab will be administered as a subcutaneous injection for 24 weeks

Treatment:

Drug: Obexelimab

Placebo

Placebo Comparator group

Description:

Placebo will be administered as a subcutaneous injection for 12 weeks

Treatment:

Drug: Placebo