Christophe Arbet-Engels
AltimmuneAbout Christophe Arbet-Engels
Christophe Arbet-Engels, M.D., Ph.D., was appointed Chief Medical Officer (CMO) of Altimmune effective October 1, 2025, bringing 30+ years across industry, academia, and practice, with leadership through late-stage development, regulatory approvals, and launches (e.g., Xolremdi/mavorixafor approval in 2024; prior work on Lantus and Jardiance) . He holds an M.D./Ph.D. in internal medicine and endocrinology/metabolism (University of Paris) and an MBA (Rutgers), with a postdoc in endocrinology/metabolism at UC San Diego; he also serves as a Member of the Board of Tutors in Biochemical Sciences at Harvard University .
Note: Company TSR/revenue/EBITDA metrics specific to his tenure are not disclosed as of his appointment date.
Past Roles
| Organization | Role | Years | Strategic impact |
|---|---|---|---|
| X4 Pharmaceuticals (Nasdaq: XFOR) | Chief Medical Officer | 2023–2025 | Contributed to regulatory process for Xolremdi (mavorixafor) approval (2024) and led late-stage programs in chronic neutropenia . |
| Neurogastrx | Chief Medical Officer | Not disclosed | CMO responsibilities in GI/metabolic space (company bio) . |
| Millendo Therapeutics | Chief Medical Officer | Not disclosed | Late-stage development leadership (company bio) . |
| Poxel Pharmaceuticals | Chief Medical Officer & EVP Late Development/Medical Affairs | Appointed 2017 | Led imeglimin Phase 3; leadership includes diabetes/CV development; later associated with Twymeeg approval in Japan . |
| Biogen; Boehringer Ingelheim; Hoffmann-La Roche; Merck Research Labs; Aventis/Sanofi; Ligand | Senior medical/clinical leadership roles | Not disclosed | Led development/registration/launch/lifecycle mgmt (including Lantus and Jardiance) . |
External Roles
| Organization | Role | Years | Strategic impact |
|---|---|---|---|
| Harvard University | Member, Board of Tutors in Biochemical Sciences | Not disclosed | Academic mentorship and advisory role . |
| The Salk Institute; University of Paris VI; Assistance Publique–Hôpitaux de Paris | Educational/research roles | Not disclosed | Academic and clinical education roles . |
Fixed Compensation
| Component | Detail |
|---|---|
| Base salary | Not disclosed in SEC filings or company releases as of appointment. The October 3, 2025 8-K references his appointment but does not detail his compensation terms . |
| Target annual bonus % | Not disclosed (company’s program pays annual performance-based bonuses vs corporate objectives; see Performance Compensation) . |
| Benefits/perquisites | Standard executive benefits program disclosed for NEOs (health/HSA match; 401(k) match). Individual CMO-specific perqs for Arbet-Engels are not disclosed . |
Performance Compensation
Altimmune funds NEO annual bonuses based on corporate objectives; for FY2024, the Compensation Committee set weighted goals and approved ~95% achievement for management (context for the CMO role; applies to 2024 NEOs, not to Arbet-Engels who joined in Oct-2025) .
| Metric (FY2024) | Weighting | Target | Actual/Assessment | Payout Basis |
|---|---|---|---|---|
| Strategic partnerships to maximize program value | 40% | Target level defined by Comp Committee | Committee/Board assessed aggregate achievement; total corporate bonus funding at ~95% of target | ~95% company-level funding for NEOs . |
| Advance development of pemvidutide for MASH | 30% | Target level defined | As above | As above . |
| Additional programs for pemvidutide | 15% | Target level defined | As above | As above . |
| Manage operations to maximize resources/minimize risk | 15% | Target level defined | As above | As above . |
Notes: Below target = 0–80%; meet = 80–120%; exceed = 120–150% weighting; overall 2024 achievement ~95% .
Equity Ownership & Alignment
| Item | Detail |
|---|---|
| Inducement equity grant (new-hire) | Options to purchase 450,000 shares; 150,000 RSUs granted in connection with CMO appointment . |
| Vesting – Options | 25% vests at first anniversary of Grant Date; remaining 75% vests monthly (1/36th) thereafter through the fourth anniversary, subject to continued employment . |
| Vesting – RSUs | 25% vests at first anniversary of Grant Date; remaining 75% vests in three substantially equal annual installments through the fourth anniversary, subject to continued employment . |
| Current beneficial ownership | Not disclosed in 2025 proxy table (snapshot as of Aug 1, 2025 predates his Oct 1 start); NEO ownership table lists then-current officers/directors only . |
| Hedging/derivatives policy | Company insider trading policy expressly prohibits short sales and derivative or other hedging transactions by executive officers, directors, and employees . |
| Pledging policy | Policy highlights risks of margin/pledging; explicit prohibition stated for hedging/derivatives; pledge prohibition is not expressly stated in the cited section . |
| Ownership guidelines | No executive ownership multiple is disclosed in the cited sections; not found in the 2025 proxy excerpts provided . |
Insider selling pressure analysis:
- First vesting for both RSUs and options occurs at the 1-year anniversary of the Grant Date, creating a concentrated potential sell/withhold event at year 1 (tax withholding for RSUs typically satisfied via share withholding; options require cash to exercise) .
- Thereafter, monthly option vesting may create steady-state incremental sell pressure if exercises occur, whereas RSUs release annually (three installments after Year 1), causing lumpier events .
Employment Terms
| Topic | Detail |
|---|---|
| Start date | Effective October 1, 2025, appointed as Chief Medical Officer . |
| Offer letter / employment agreement | Not publicly filed as of the October 3, 2025 8-K; compensation and severance terms for Arbet-Engels were not disclosed in that filing . |
| Typical Altimmune CMO terms (reference – predecessor) | Predecessor CMO (Dr. M. Scott Harris) employment agreement provided: 6 months’ base salary and 6 months health coverage upon termination without cause/for good reason (pre-CIC), and 12 months’ base salary plus target bonus, 6 months health coverage, and full acceleration of unvested equity upon qualifying termination within 1-year post-CIC; subject to release; 280G cutback applies . |
| Transition context (predecessor) | Dr. Harris moved to Senior Strategic Advisor effective Oct 1, 2025, with continued vesting through Feb 28, 2026, extended option exercise window to 12 months post-separation, and eligibility for full 2025 cash bonus subject to criteria . |
| Restrictive covenants | For prior NEOs, non-solicitation and certain restrictions applied post-termination; specific non-compete/scope for Arbet-Engels not disclosed . |
| Clawback | Company has a Nasdaq-compliant clawback policy for financial restatements (applies to current/former executive officers) . |
Track Record, Value Creation, and Execution Risk
- Regulatory/late-stage track record: Led or contributed to approvals and launches (e.g., Xolremdi approval 2024; prior leadership on Lantus and Jardiance), relevant to Altimmune’s planned Phase 3 pemvidutide program in MASH .
- Program momentum: Company reiterated near-term milestones (EOH2 2025 48-week IMPACT data; End-of-Phase-2 FDA meeting), with Arbet-Engels charged to lead clinical development .
- Legal overhang: Multiple class-action notices/lawsuits were announced in Sep–Oct 2025 following MASH IMPACT 24-week topline statistical issues; stock fell >50% on June 26, 2025—this is a company-level risk context, not specific to Arbet-Engels .
Investment Implications
- Alignment and retention: A front-loaded inducement package (450k options; 150k RSUs) with four-year vesting and a one-year initial cliff strongly ties retention and incentives to long-term value creation; hedging/derivative prohibitions support alignment, while pledging stance is not explicitly prohibited in cited policy language .
- Sell-pressure mechanics: Expect potential liquidity events around the first anniversary (25% cliffs) and subsequently monthly (options) vs annual (RSUs); share withholding for RSUs at vest can impact float; monitor Form 4s around vest dates .
- Execution credibility: His late-stage/regulatory background (including recent approval experience) is additive for MASH/AUD/ALD programs; successful FDA alignment and Phase 3 design choices will be key catalysts under his leadership .
- Pay-for-performance framing: Company-wide bonus design (weights on partnerships, MASH progress, program expansion, operating discipline) and a clawback policy indicate a structured framework; say-on-pay support was 63.1% in 2024, suggesting investor scrutiny of pay outcomes versus results remains elevated .
Near-term diligence items: watch for (i) any subsequent 8-K/offer letter disclosures for CMO base/bonus/severance terms, (ii) Form 4 filings for grant dates/prices and any 10b5-1 adoptions, and (iii) outcomes of the EOP2 meeting and 48-week IMPACT data readout under the new CMO’s oversight .
