Aperture

Neuromuscular · Rare · teaser

Spinal muscular atrophy

Updated August 2026 · SMN1 (5q)

Teaser case. Selected price and peak-sales fields are held for a paid Brief — the rest is the method.

Thesis

SMA is the rare-disease case study everyone cites — three approved SMN-restoring medicines, newborn screening, infants who now walk. The Corp Dev question in 2026 is no longer 'does the category work?' It is 'where is residual value after Zolgensma, Evrysdi and Spinraza have split the incident pie, and what does the next mechanism have to do?'

Birth incidence

~1 / 10,000

7MM treated (dir.)

High capture

Incident Type 1 near-standard

Approved SMN Rx

4

Spinraza, Zolgensma, Evrysdi, Itvisma

NBS coverage

Broad US / uneven EU

Residual unmet

Function, not survival

Market shape

Incident + chronic stack

So-what for Corp Dev

  1. 01Incident Type 1 is largely captured. The fight is combination use, older prevalent patients, and non-5q / residual weakness.
  2. 02Oral Evrysdi took share from chronic intrathecal Spinraza. Any new chronic must beat a daily syringe at home.
  3. 03Itvisma (higher-dose / broader onasemnogene) is Novartis defending the GT franchise, not opening a new one.
  4. 04Unmet need has moved from survival to fatigue, bulbar function, and the adults NBS never saw.

Residual unmet need

  • Prevalent adults and Type 3/4

    NBS and early GT transformed Type 1. Adults diagnosed before the SMN era remain under-treated and under-modelled.

  • Residual motor and bulbar deficit

    SMN restoration is not a cure. Fatigue, scoliosis, bulbar and respiratory needs persist — the next wave is muscle-directed.

  • Combination and sequencing

    GT then oral? Oral forever? Re-dosing is not an option. Guidelines are still local practice.

Marketed share (dir.)

  • Evrysdi41%
  • Spinraza28%
  • Zolgensma22%
  • Itvisma9%
Algorithm

Late pipeline

  • Higher-dose nusinersen

    Biogen · Phase 3 · ASO / exon skip

Full pipeline

Asset dives

Case study with selected commercial fields held back. Full Brief unlocks the model.