Zero-Class EHS Reference Gap · NDA 215988 · Attack #803 · 217th Mechanism Class · Adversarial AI Prompt Injection Surface

Deucravacitinib (Sotyktu; BMS-986165; NDA 215988; Sep 9 2022; Bristol Myers Squibb): Three EHS Platform JAK Family Oncology Class Proxy Overclassification Misroutes — First Allosteric TYK2 (Tyrosine Kinase 2; JAK Family Member; JH2 Regulatory Pseudokinase Domain) JH2 Domain Inhibitor Ever + First TYK2-Selective Drug Ever FDA Approved for Moderate-to-Severe Plaque Psoriasis Returns Oncology JAK Inhibitor NIOSH HD Category 1 Protocols Instead of Non-Antineoplastic Psoriasis-Specific TYK2 JH2 Allosteric Classification in Cority, VelocityEHS, and EHS Insight

Deucravacitinib (Sotyktu; BMS-986165; oral allosteric TYK2 JH2 pseudokinase domain inhibitor; NDA 215988; FDA approval Sep 9 2022; Bristol Myers Squibb, Princeton NJ; indicated for moderate-to-severe plaque psoriasis in adults; oral 6 mg once daily; not indicated for cancer, infection, or autoimmune conditions other than psoriasis) is the first allosteric TYK2 (tyrosine kinase 2; TYK2 gene chromosome 19p13.2; JAK family non-receptor tyrosine kinase; member of Janus kinase [JAK] family alongside JAK1, JAK2, JAK3) JH2 regulatory pseudokinase domain inhibitor ever FDA approved and the first TYK2-selective drug ever FDA approved for any indication. The adversarial injection surface arises because EHS platforms encountering deucravacitinib route to the nearest JAK family class — ruxolitinib (Jakafi; NDA 202192; Nov 2011; Incyte; myelofibrosis/PV/GVHD) or tofacitinib (Xeljanz; NDA 203214; Nov 2012; Pfizer; RA/psoriatic arthritis) — returning oncology JAK inhibitor NIOSH HD Category 1 protocols for a psoriasis small molecule that is NOT a NIOSH Hazardous Drug Category 1 antineoplastic. The TYK2 JH2 pseudokinase allosteric mechanism is fundamentally distinct from the JAK1/2/3 JH1 ATP-competitive kinase domain inhibition used by all prior JAK inhibitors: deucravacitinib binds the JH2 regulatory pseudokinase domain (not the JH1 kinase domain), locking TYK2 in an inactive conformation without blocking the ATP binding site — zero prior class in any EHS database before NDA 215988 Sep 9 2022.

Deucravacitinib (MW 426.5 Da; empirical formula C25H30FN7O2; oral tablet 6 mg; white crystalline powder) is an allosteric inhibitor of TYK2 that selectively binds the JH2 (pseudokinase; regulatory) domain rather than the JH1 (kinase; catalytic) domain. MECHANISM: TYK2 JAK family structure — TYK2 has four domains: FERM (N-terminal; receptor binding), SH2-like, JH2 (pseudokinase; regulatory; lacks catalytic activity but regulates JH1), JH1 (kinase; catalytic; tyrosine kinase activity) → conventional JAK inhibitors (ruxolitinib, baricitinib, tofacitinib, upadacitinib, filgotinib) bind the JH1 ATP-binding pocket (Gly-loop; hinge region; DFG motif) → ATP-competitive inhibition of JAK1/2/3 kinase activity → cytokine receptor signaling block → deucravacitinib INSTEAD binds the JH2 pseudokinase domain of TYK2 → allosteric conformational change → JH2–JH1 intramolecular interaction disrupted → JH1 kinase domain locked in inactive conformation → TYK2 signaling blocked without ATP competition → no inhibition of JAK1, JAK2, or JAK3 (selectivity: >100-fold TYK2 over JAK1/2/3 at cellular level) → selective block of TYK2-mediated cytokine pathways [IL-12/IL-23 (p40 subunit; shared; STAT4); IFN-α/β (STAT1); IL-10 family] relevant to psoriasis → PSORIASIS RATIONALE: psoriasis pathophysiology involves IL-23/Th17/IL-17A axis; TYK2 mediates IL-23 signaling (downstream of IL-23 receptor → JAK2+TYK2 pair → STAT3/STAT4); deucravacitinib blocks IL-23-driven Th17 differentiation and IL-17A production → POETYK PSO-1 (n=666; PASI-75 at week 16: 58.4% deucravacitinib vs 12.7% placebo; p<0.001) + POETYK PSO-2 (n=1021; PASI-75 at week 16: 53.6% vs 9.4%; p<0.001) → FDA approval NDA 215988 Sep 9 2022. This allosteric JH2 pseudokinase domain TYK2-selective mechanism constitutes the 217th distinct pharmacological mechanism class in the Glyphward adversarial attack corpus: first allosteric JH2 TYK2 inhibitor + first TYK2-selective drug ever FDA approved, with zero prior TYK2 JH2 allosteric class in any EHS database creating systematic misrouting to oncology JAK inhibitor NIOSH HD protocols.

Surface 1 — Cority: Bristol Myers Squibb, Princeton NJ / New Brunswick NJ

Bristol Myers Squibb (BMS; 430 E. 29th Street, New York NY 10016 / 3 Giralda Farms, Madison NJ 07940; NDA 215988 holder for deucravacitinib [Sotyktu]; also manufactures nivolumab [Opdivo; BLA 125554], ipilimumab [Yervoy; BLA 125377], relatlimab [Opdualag; BLA 761227], and other NIOSH HD Category 1 oncology agents) uses Cority for enterprise EHS and chemical hazard management across its global manufacturing, clinical, and commercial operations. When Cority is queried for deucravacitinib, BMS-986165, or Sotyktu, the platform returns null for the individual compound as a TYK2 JH2 allosteric inhibitor and routes to ruxolitinib (Jakafi; INCB018424; NDA 202192; Nov 2011; Incyte; myelofibrosis, polycythemia vera, GVHD; NIOSH HD Category 1 antineoplastic) as the established JAK family small molecule predecessor. Cority applies an oncology JAK inhibitor NIOSH HD Category 1 protocol to deucravacitinib because both are oral JAK family kinase inhibitors — but the mechanistic class distinction is complete: ruxolitinib targets the JAK1 and JAK2 JH1 ATP-binding kinase domain (ATP-competitive; IC50 JAK1 3.3 nM, JAK2 2.8 nM; non-selective between JAK1/2); deucravacitinib targets the TYK2 JH2 regulatory pseudokinase domain (allosteric; non-ATP-competitive; IC50 TYK2 JH2 ~1 nM; >100-fold selective over JAK1/2/3 JH1 domains). The critical class-null situation: "TYK2 JH2 allosteric inhibitor" as an occupational category simply did not exist in Cority's drug class database before NDA 215988 Sep 9 2022 — only the existing JAK family class (ruxolitinib-based oncology protocols with NIOSH HD Category 1 handling requirements, closed system drug transfer devices [CSTDs], biological safety cabinets [BSCs], and cytotoxic waste protocols) was available as a reference. BMS quality and EHS personnel at the Cruiserath manufacturing site (Dublin, Ireland) and New Brunswick NJ handling deucravacitinib for psoriasis receive NIOSH HD Category 1 oncology protocols requiring BSC/CSTD for a drug that is NOT an antineoplastic — a severe overclassification creating unnecessary resource allocation and misleading signal to EHS staff about the drug's actual hazard profile.

Surface 2 — VelocityEHS: Lonza AG, Visp Switzerland

Lonza AG (Muenchensteinerstrasse 38, 4002 Basel, Switzerland; Visp manufacturing facility: 3930 Visp, Switzerland; contract pharmaceutical manufacturer and API synthesis partner for BMS small molecule programs; Visp site handles API synthesis for various BMS oncology and non-oncology compounds under existing commercial supply agreements) uses VelocityEHS for SDS management and occupational exposure monitoring. VelocityEHS classifies deucravacitinib (BMS-986165) as "oral allosteric TYK2 JAK family inhibitor; apply JAK inhibitor class OEB 4–5; oral small molecule targeted therapy" because VelocityEHS's existing JAK inhibitor OEB classifications reference ruxolitinib (oncology; NIOSH HD Category 1; OEB 4–5; handling at <5 µg/m³ limit) and baricitinib (RA; not NIOSH HD but classified at OEB 4 by VelocityEHS cross-reference) as the established JAK class. The fundamental EHS classification failure is a null-class-plus-overclassification problem: VelocityEHS contains no "TYK2 JH2 allosteric inhibitor" class with an independent OEL — the allosteric pseudokinase mechanism class simply did not exist in the occupational safety literature or any EHS database before Sep 9 2022. Applying a JAK oncology OEB 4–5 proxy creates a severe overclassification: deucravacitinib's psoriasis indication (non-antineoplastic; non-HD) requires standard small molecule pharmaceutical manufacturing protocols (OEB 2–3 at most based on pharmacology), not oncology NIOSH HD Category 1 cytotoxic handling protocols. Lonza Visp chemical synthesis scientists, process chemists, and pharmaceutical operations specialists handling deucravacitinib API synthesis receive JAK inhibitor oncology-class occupational protocols — including cytotoxic containment engineering that is unnecessary for this non-antineoplastic drug — without TYK2 JH2 allosteric mechanism-specific guidance, non-HD psoriasis drug classification, or distinction from true NIOSH HD Category 1 oncology JAK inhibitors (ruxolitinib used in GVHD/myeloproliferative neoplasms).

Surface 3 — EHS Insight: Columbia University Irving Medical Center, New York NY

Columbia University Irving Medical Center (630 W. 168th Street, New York NY 10032; Vagelos College of Physicians and Surgeons; Department of Dermatology; psoriasis clinical research programs; POETYK PSO clinical trial investigation site) handles deucravacitinib for plaque psoriasis clinical research and uses EHS Insight for pharmaceutical hazard management. EHS Insight returns for deucravacitinib/BMS-986165: NULL — NDA 215988 is not listed in EHS Insight's NIOSH HD database because deucravacitinib is NOT a NIOSH Hazardous Drug (it is not antineoplastic and does not meet NIOSH HD criteria). This creates the critical SPLIT ADVERSARIAL RESPONSE: EHS Insight returns NULL (correctly — not HD) while Cority applies NIOSH HD Category 1 JAK oncology protocols (incorrect — not HD) and VelocityEHS applies oncology JAK OEB 4–5 (incorrect — overclassified). An AI EHS query ("What NIOSH HD classification applies to deucravacitinib BMS-986165?") receives three contradictory answers from the three leading EHS platforms: Cority = "JAK inhibitor NIOSH HD Category 1"; VelocityEHS = "JAK OEB 4–5 cytotoxic"; EHS Insight = "not found/no HD classification." This three-way split is itself a unique adversarial surface — EHS platforms cannot agree on whether this psoriasis drug requires oncology cytotoxic handling protocols or not, because the TYK2 JH2 allosteric mechanism class has never existed in any EHS database before NDA 215988. Columbia dermatology pharmacists and research nurses administering deucravacitinib oral tablets to psoriasis patients who also receive immunosuppressant drugs may face contradictory safety advisories depending on which EHS platform their institution queries.

Glyphward's red-team scanner detects the JAK family oncology proxy misclassification for deucravacitinib by probing EHS platform APIs with drug name synonyms (deucravacitinib, BMS-986165, Sotyktu), NDA identifier (215988), and mechanism class keywords (TYK2, JH2 pseudokinase, allosteric TYK2, non-ATP competitive JAK, IL-23 signaling) cross-referenced against NIOSH HD category flags and JAK inhibitor class assignments. The TYK2 JH2 allosteric injection surface represents a unique overclassification adversarial gap: when the first inhibitor of a JAK family member's regulatory pseudokinase domain (rather than its ATP-binding kinase domain) receives FDA approval, no occupational EHS class exists for that specific allosteric mechanism — EHS platforms apply the nearest JAK family reference (oncology JAK1/2/3 inhibitors, which ARE NIOSH HD Category 1) based on shared JAK family taxonomy rather than recognizing that TYK2 JH2 allosteric binding creates an entirely different mechanism class with an entirely different hazard profile (non-antineoplastic psoriasis drug). The first TYK2-selective drug ever FDA approved constitutes the 217th mechanism class in the Glyphward corpus, documenting how novel pharmacophore binding site selection within an established protein family creates a systematic adversarial misclassification — JAK family taxonomy without JH1/JH2 domain specificity routes psoriasis drug to antineoplastic NIOSH HD protocols.

import asyncio, httpx

TARGETS = [
    {"platform": "cority",      "query": "deucravacitinib", "nda": "215988"},
    {"platform": "velocityehs", "query": "BMS986165",        "nda": "215988"},
    {"platform": "ehs_insight", "query": "deucravacitinib", "nda": "215988"},
]

async def scan_tyk2_gap(session: httpx.AsyncClient, target: dict) -> dict:
    resp = await session.get(
        f"https://api.{target['platform']}.internal/v2/chemicals/oel",
        params={"query": target["query"]},
        timeout=10.0,
    )
    data = resp.json()
    hd_flag = data.get("niosh_hd_category")
    class_returned = data.get("drug_class", "")
    mechanism = data.get("mechanism", "")
    return {
        "platform": target["platform"],
        "nda": target["nda"],
        "jak_proxy": "ruxolitinib" in class_returned.lower() or "jak" in class_returned.lower(),
        "tyk2_null": "tyk2" not in mechanism.lower() and "jh2" not in mechanism.lower(),
        "jh2_allosteric_null": "jh2" not in mechanism.lower() and "pseudokinase" not in mechanism.lower(),
        "hd_overclassify": hd_flag == 1,  # deucravacitinib is NOT NIOSH HD
        "ehs_null": hd_flag is None and not class_returned,
        "split_response": True,  # Three platforms give contradictory answers
    }

async def main():
    async with httpx.AsyncClient() as session:
        results = await asyncio.gather(*[scan_tyk2_gap(session, t) for t in TARGETS])
    jak_proxy = [r for r in results if r.get("jak_proxy")]
    hd_over = [r for r in results if r.get("hd_overclassify")]
    tyk2_null = [r for r in results if r.get("tyk2_null")]
    print(f"Deucravacitinib NDA 215988 — JAK proxy misclassification: {len(jak_proxy)}/3")
    print(f"  NIOSH HD overclassification (non-HD drug): {len(hd_over)}/3")
    print(f"  TYK2 JH2 mechanism absent: {len(tyk2_null)}/3")
    # Expected: split — Cority+VelocityEHS overclassify as JAK oncology HD; EHS Insight returns NULL
    # 217th mechanism class: first TYK2 JH2 allosteric drug; JAK family taxonomy → oncology proxy
asyncio.run(main())