AB Science is a French pharmaceutical company headquartered in Paris, France, dedicated to developing innovative therapies for severe diseases, with particular focus on oncology and neurodegenerative disorders. Founded in 2001, the company is listed on Euronext Paris (ticker: AB) and has pioneered the development of selective tyrosine kinase inhibitors that target mast cells and microglia-mediated neuroinflammation.
The company's lead compound, masitinib (AB1010), represents a novel approach to treating amyotrophic lateral sclerosis (ALS) and Alzheimer's disease by targeting the neuroimmune axis through inhibition of mast cell activation and associated neuroinflammatory pathways.
| Attribute |
Details |
| Ticker |
Euronext Paris: AB |
| Headquarters |
Paris, France |
| Founded |
2001 |
| CEO |
Alain Moussy |
| Focus Areas |
Tyrosine kinase inhibitors, neuroinflammation, oncology |
| Employees |
~100 |
| Market Cap |
~€200-300M (as of 2024) |
| Listed |
Euronext Paris since 2010 |
¶ History and Milestones
¶ Company Foundation and Early Development (2001-2015)
AB Science was established in 2001 with a focus on developing selective tyrosine kinase inhibitors. The company's platform technology centered on targeting mast cells through c-Kit inhibition, initially exploring applications in oncology and inflammatory conditions.
Key milestones:
- 2001: Company founded in Paris
- 2005: Initiation of masitinib development program
- 2010: IPO on Euronext Paris
- 2014: Initiation of ALS Phase 3 clinical trial (AB10015)
- 2015: Initiation of Alzheimer's disease Phase 2 clinical trial
The company's clinical development program has focused on repositioning masitinib for neurodegenerative diseases:
- 2016: Phase 3 ALS trial completes enrollment
- 2019: Top-line results announced for ALS Phase 3
- 2020: Regulatory submissions in Europe for ALS
- 2021: Continued development of Alzheimer's program
- 2022-2024: Ongoing regulatory discussions and potential re-submission strategies
AB Science's technology platform is based on selective tyrosine kinase inhibitors that modulate the neuroimmune response through targeted inhibition of mast cells and microglia activation pathways.
The platform targets:
- Mast Cell Activation: Inhibition of c-Kit and PDGFR signaling reduces mast cell degranulation and associated neuroinflammation
- Microglial Modulation: Src family kinase inhibition (Lyn/Fyn) reduces microglial activation in the CNS
- Neuroprotection: Combined anti-inflammatory and neuroprotective mechanisms
Masitinib is a selective tyrosine kinase inhibitor with the following molecular targets:
| Target |
Pathway |
Biological Effect |
| c-Kit |
Stem cell factor receptor |
Mast cell survival and activation inhibition |
| PDGFR-α/β |
Platelet-derived growth factor |
Reduced fibroblast activation, anti-inflammatory |
| Lyn/Fyn |
Src family kinases |
Microglial activation modulation |
The multi-target approach distinguishes masitinib from single-target anti-inflammatory agents, potentially providing broader neuroprotective effects in neurodegenerative diseases.
Masitinib binds to the ATP-binding site of target kinases, competitively inhibiting phosphorylation of downstream substrates. This mechanism:
- Reduces release of pro-inflammatory cytokines (TNF-α, IL-1β, IL-6)
- Decreases mast cell degranulation and histamine release
- Modulates microglial phenotype from M1 (pro-inflammatory) to M2 (neuroprotective)
- May promote neurogenesis through reduced neuroinflammation
| Drug |
Mechanism |
Target |
Phase |
Indication |
Status |
| Masitinib (AB1010) |
Tyrosine kinase inhibitor |
c-Kit, PDGFR, Lyn/Fyn |
Phase 3 |
ALS |
Pending regulatory decision |
| Masitinib (AB1010) |
Anti-inflammatory/neuroprotective |
Neuroinflammation |
Phase 2 |
Alzheimer's disease |
Completed |
| AB1010 (veterinary) |
c-Kit inhibitor |
c-Kit |
Approved |
Veterinary oncology |
Marketed |
The Phase 3 trial (NCT02588677) evaluated masitinib in combination with standard of care (riluzole) in patients with ALS.
Trial Design:
- Enrollment: 425 patients with definite or probable ALS
- Treatment: Masitinib (4.5 mg/kg/day) + riluzole vs. placebo + riluzole
- Duration: 48 weeks
- Primary Endpoint: Change in ALSFRS-R score
- Secondary Endpoints: Slow vital capacity (SVC), manual muscle testing (MMT)
Efficacy Results:
- Primary endpoint did not meet statistical significance in overall population
- Pre-specified subgroup analysis showed meaningful benefit in patients with 'definite' ALS diagnosis
- Slower disease progression observed in certain patient subgroups
- Biomarker analysis suggested reduced neuroinflammation markers
Regulatory Status:
- European Medicines Agency (EMA) evaluated the application
- Additional data requested to confirm benefit-risk profile
- Company continues to pursue approval pathways
The ALS treatment landscape includes:
| Company |
Drug |
Mechanism |
Status |
| Amylyx |
AMX0035 |
Neuroprotection |
Approved (2022) |
| Biogen |
Tofersen |
SOD1 ASO |
Approved (2023) |
| Cytokinetics |
Reldesomt |
Muscle function |
Phase 3 |
| Denali Therapeutics |
DNL151 |
LRRK2 inhibitor |
Phase 2 |
| AB Science |
Masitinib |
Kinase inhibition |
Phase 3 |
AB Science conducted a Phase 2 clinical trial evaluating masitinib in patients with mild-to-moderate Alzheimer's disease.
Trial Design:
- Enrollment: ~250 patients with AD (MMSE 16-26)
- Treatment: Masitinib at two dose levels
- Duration: 24 weeks
- Primary Endpoints: Safety, tolerability, cognitive measures (ADAS-Cog)
Results:
- Acceptable safety and tolerability profile
- Signals of cognitive stabilization observed
- Dose-dependent effects on neuroinflammation biomarkers
Current Status:
- Phase 2 completed
- Company evaluating Phase 3 feasibility
- Partnering opportunities under exploration
Mast cells are increasingly recognized as playing important roles in neuroinflammation and neurodegeneration:
- Location: Mast cells reside in the meninges and perivascular spaces adjacent to the CNS
- Activation: Environmental triggers, stress, and disease states activate mast cells
- Mediators: Activated mast cells release histamine, TNF-α, proteases, and other pro-inflammatory molecules
- Interaction: Mast cells communicate with microglia and neurons, amplifying neuroinflammation
The rationale for using tyrosine kinase inhibitors in neurodegenerative disease includes:
- c-Kit inhibition: Reduces mast cell survival and activation
- PDGFR inhibition: Modulates fibroblast and glial responses
- Src family inhibition: Directly reduces microglial activation
- Combined effect: Broader anti-inflammatory spectrum than single-target approaches
¶ ALS Competitive Landscape
AB Science's masitinib occupies a unique position in the ALS competitive landscape:
Advantages:
- Novel mechanism targeting neuroinflammation through mast cells
- Oral administration (vs. intravenous for some competitors)
- Established safety profile from oncology and veterinary use
- Potential for combination with existing therapies
Challenges:
- Regulatory hurdles based on Phase 3 results
- Competition from recently approved therapies (AMX0035, tofersen)
- Need for biomarker-based patient selection
| Approach |
Target |
AB Science Differentiator |
| Anti-aggregates |
Aβ, Tau |
Targets upstream neuroinflammation |
| Gene therapy |
Specific mutations |
Small molecule, oral delivery |
| Cell therapy |
Cell replacement |
Disease-modifying through immunomodulation |
| Symptomatic |
Dopamine/glutamate |
Disease-modifying potential |
AB Science is a publicly traded company on Euronext Paris. The company has historically funded operations through:
- Equity offerings (multiple rounds since IPO)
- Grant funding for clinical trials
- Potential future partnership revenues
Financial Highlights (as publicly reported):
- Cash runway through 2024-2025 based on current programs
- R&D expenses focused on masitinib clinical development
- No significant revenue from therapeutic products (veterinary only)
- ALS Regulatory Decision: Awaiting potential EMA decision on masitinib for ALS
- Phase 3 Re-trial: Potential for additional Phase 3 trial with refined endpoints
- Alzheimer's Phase 3: Planning for pivotal Phase 3 trial based on Phase 2 results
- Partnership Opportunities: Exploring co-development or licensing agreements
- Combination Therapies: Investigating masitinib with other pipeline agents
- Regulatory announcements for ALS indication
- Alzheimer's disease Phase 3 trial initiation
- Partnership or licensing announcements
- Clinical data publications in peer-reviewed journals