AB SCIENCE (AB) Corporate presentation summary

Portfolio and funding

• Masitinib has Phase 3 programs authorized by EMA and FDA in ALS, progressive MS and Alzheimer’s disease; AB8939 is in Phase 1 in AML, with Phase 1 expansion fully financed.

• Masitinib is also in Phase 2 for sickle cell disease, funded through a €9M grant; cash runway is stated to exceed 12 months.

• Funding is being sought for the ALS Phase 3 program, with plans to partner the MS and Alzheimer’s Phase 3 programs.

• Masitinib is designed to target mast-cell kinases and MCSFR-1 in macrophages and microglia; animal-model data include prolonged survival and restored motor function.

Masitinib in ALS

• Phase 2B enrolled 394 patients; in the prespecified normal-progressor population, the 4.5 mg/kg/day dose showed a 27% difference in ALSFRS-R deterioration slope vs placebo (mLOCF, p=0.0157).

• Secondary results included ALSAQ-40 benefit (p=0.0078), FVC benefit (p=0.0296), PFS gain of 4 months (p=0.0159) and EFS gain of 3 months (p=0.0162).

• A subgroup with ALSFRS-R scores above zero on all items showed stronger results, including a 20.2% relative CAFS benefit (p=0.0290) and median PFS of 25 vs 16 months (p=0.0057).

• EMA considered the safety profile acceptable for further ALS trials; the safety database included 4,318 randomized patients.

• EMA- and FDA-authorized Phase 3 plans 408 patients randomized 1:1, 48-week treatment, with CAFS as the FDA primary endpoint and ALSFRS-R change as the EMA primary endpoint.

• Assuming study initiation in Q1 2026, the stated plan targets Phase 3 readout by Q4 2028, early access in Q2 2029 and launch by end-2029; projected peak sales are €2B if approved.

AB8939 in AML

• AB8939 combines microtubule disruption with ALDH inhibition, targeting proliferating leukemia cells and leukemia stem cells; it is described as not subject to P-glycoprotein-mediated multidrug resistance.

• Monotherapy Phase 1 is complete and combination Phase 1 has begun, including AB8939 with venetoclax, with or without azacitidine.

• In the first four reported AB8939-plus-venetoclax patients, outcomes included one CRi and three partial remissions; no toxicity or DLT was reported.

• The targeted high-risk AML population is estimated at ~50% of patients; projected potential market size is €2.2B annually.