Retention on first-line biologics in generalized myasthenia gravis sits at 90% in US practice, with Alexion’s Ultomiris and argenx’s Vyvgart (IV) leading use; more than two in five audited patients are on an efgartigimod formulation. The findings are based on 436 patient charts and inputs from 92 neurologists and neuromuscular specialists.
The new Spherix Global Insights analysis underscores a market that is both consolidating around two incumbents and expanding earlier in the treatment journey. Physicians report broad satisfaction with current brands and low propensity to switch, even as targeted biologics are being initiated sooner. A late-stage pipeline is building, with inebilizumab (Uplizna), gefurulimab, and cemdisiran emerging as top future considerations among clinicians reviewing specific patient profiles. Yet the bar for adoption is clear: candidates will need to demonstrate meaningful differentiation on efficacy, durability, convenience, or payer positioning to displace established agents.
Strategically, this is a classic defend-and-expand dynamic. Incumbents benefit from high persistence, strong physician familiarity, and mature access infrastructure. New entrants face a funnel that rewards winning incidents or early-line patients rather than orchestrating switches. That shifts development emphasis toward earlier-line trials, durable response data, and steroid-sparing outcomes that resonate with both clinicians and payers. Dosing convenience alone is unlikely to move share in the absence of a tangible clinical or economic delta, particularly given entrenched support programs and infusion center workflows already calibrated to current brands.
For sites, earlier biologic initiation broadens the pool of eligible patients and frontloads operational work: accelerated diagnostic confirmation, payer authorization, and onboarding to infusion or subcutaneous regimens. Subcutaneous formulations and long-acting modalities promise scheduling flexibility, but they also reconfigure staffing, training, and monitoring needs. With high on-drug retention, switch-focused studies will be harder to recruit ethically and operationally; pragmatic designs that capture add-on strategies, steroid tapering, or rescue therapy avoidance may be more feasible than wholesale brand swaps.
Sponsors and CROs should plan for incident-patient capture rather than churn-based recruitment. Community neurology networks become critical, as does rapid referral infrastructure from general neurology to specialty centers. Expect payers to amplify demands for head-to-head or robust indirect comparisons, durability beyond 6–12 months, corticosteroid minimization, and reductions in IVIg or plasma exchange utilization. Regulators’ comfort with earlier use will hinge on sustained safety and consistent effects across serotypes, with particular scrutiny on AChR-positive populations for complement pathway agents and broader applicability for FcRn or B-cell–directed approaches.
The next catalyst will be readouts and labels that explicitly target earlier lines, self-administration, or less frequent dosing while delivering credible superiority or cost offsets. Watch for whether any entrant runs an active-comparator study against efgartigimod or a C5 inhibitor, or instead leans on optimized endpoints, composite functional scores, and health economics to secure payer traction. If siRNA or B-cell–directed mechanisms can pair quarterly or semiannual dosing with durable MG-ADL and QMG gains and steroid-sparing, the infusion-center calculus could change quickly. Until then, share shifts will be incremental and tied to new starts, and operational winners will be those who streamline access, compress time-to-first-dose, and build community-based pipelines for earlier biologic adoption.
Jon Napitupulu is Director of Media Relations at The Clinical Trial Vanguard. Jon, a computer data scientist, focuses on the latest clinical trial industry news and trends.
