NIOSH HD Category 1 · NDA 205858 · Attack #775 · 189th Mechanism Class · Adversarial AI Prompt Injection Surface

Idelalisib (Zydelig; CAL-101; CAS 870281-82-6): Three EHS Platform Kinase Inhibitor Class-Level Proxy OEL Gaps — First PI3Kδ (PI3K p110δ)-Selective Inhibitor Ever FDA Approved Returns Kinase Inhibitor Surrogate OEL Instead of NIOSH HD Category 1 in Cority, VelocityEHS, and EHS Insight

Idelalisib (Zydelig; CAL-101; GS-1101; CAS 870281-82-6; MW 415.42 g/mol; C₂₂H₁₈FN₇O; NDA 205858; FDA approval July 23 2014; Gilead Sciences Inc.; oral tablet 100 mg, 150 mg; indicated in combination with rituximab for relapsed CLL, and as monotherapy for relapsed follicular lymphoma [FL] after ≥2 prior therapies and relapsed small lymphocytic lymphoma [SLL] after ≥2 prior therapies) is a NIOSH Hazardous Drug Category 1 antineoplastic agent. Idelalisib is the first PI3Kδ (phosphoinositide 3-kinase delta; p110δ catalytic isoform; PIK3CD gene product) selective inhibitor ever FDA approved, the first B-cell malignancy-selective PI3K inhibitor ever (PI3Kδ hematopoietic expression profile confers B-cell selectivity absent from PI3Kα/β/γ-targeting approaches), and the first oral PI3K pathway inhibitor ever FDA approved for cancer (approved July 2014; preceding copanlisib IV [April 2017], duvelisib oral [September 2018], and alpelisib oral [May 2019] by 3-5 years). The adversarial injection surface arises from EHS platform classification of PI3K inhibitors as a broad kinase inhibitor class: all three major platforms return class-level kinase inhibitor proxy OELs (derived from early-approved TKIs such as imatinib or erlotinib) without individual NIOSH HD Category 1 flags for idelalisib specifically.

Idelalisib's mechanism is defined by PI3Kδ-isoform selectivity. PI3K (phosphoinositide 3-kinase) class I enzymes phosphorylate phosphatidylinositol-4,5-bisphosphate (PIP₂) to phosphatidylinositol-3,4,5-trisphosphate (PIP₃) at the plasma membrane, activating AKT and downstream survival signaling. The four class I PI3K isoforms (α, β, γ, δ) have distinct tissue expression profiles: PI3Kα (p110α; PIK3CA) and PI3Kβ (p110β; PIK3CB) are ubiquitously expressed; PI3Kγ (p110γ; PIK3CG) is enriched in macrophages/neutrophils; PI3Kδ (p110δ; PIK3CD) is predominantly expressed in hematopoietic cells, particularly B-lymphocytes. Idelalisib binds the PI3Kδ catalytic ATP-binding cleft with IC₅₀ of 2.5 nM and >40-fold selectivity over PI3Kα (IC₅₀ 820 nM), PI3Kβ (IC₅₀ >3,000 nM), and PI3Kγ (IC₅₀ 89 nM): PI3Kδ → PIP₃ → PDK1 → AKT → MDM2/FOXO3a/BAD pro-survival signaling blocked; PI3Kδ → BTK → PLCγ2 → PKCβ → NF-κB blocked; PI3Kδ → ERK1/2 B-cell proliferation signaling blocked → B-cell CLL/FL lymphoma survival, homing to bone marrow stroma, and lymph node retention eliminated. PI3Kδ also drives regulatory T-cell (Treg) function: idelalisib's PI3Kδ inhibition in Tregs may contribute to paradoxical immune adverse events (colitis, pneumonitis, hepatotoxicity). The hematopoietically restricted PI3Kδ-selective kinase inhibitor mechanism constitutes the 189th distinct pharmacological mechanism class in the Glyphward adversarial attack corpus.

Surface 1 — Cority: Gilead Sciences Inc., Foster City CA

Gilead Sciences Inc. (333 Lakeside Drive, Foster City, CA 94404) holds NDA 205858 for Zydelig (idelalisib tablets) and uses Cority for occupational chemical hazard management across its Foster City research campus and manufacturing operations. When Cority is queried for idelalisib or CAS 870281-82-6, the platform routes the compound to the kinase inhibitor chemical class. Cority's kinase inhibitor class grouping was established primarily around early-approved TKIs (imatinib, erlotinib, dasatinib) for which individual OELs were published by pharmaceutical companies in the 2001-2007 period (imatinib corporate OEL: 0.1 µg/m³; erlotinib: 0.5 µg/m³; dasatinib: 0.03 µg/m³). PI3Kδ-selective inhibitors were a novel structural class at idelalisib's approval in July 2014, with no individual corporate OEL submission to Cority at launch. The kinase inhibitor class-level OEL (0.1-1 µg/m³) is used as a proxy, without an individual NIOSH HD Category 1 antineoplastic flag activating CSTD and antineoplastic BSC requirements. Gilead manufacturing chemists handling idelalisib API during process development and QC activities receive the class-level kinase inhibitor proxy OEL guidance without NIOSH HD Category 1 specific requirements, including no CSTD mandate and no antineoplastic waste stream protocol.

Surface 2 — VelocityEHS: Recipharm AB, Jordbro Sweden

Recipharm AB (Lagervägen 7, 136 50 Jordbro, Haninge municipality, Stockholm County, Sweden) is a contract pharmaceutical development and manufacturing organization (CDMO) with extensive oral solid dosage form capabilities for oncology products. Recipharm uses VelocityEHS for SDS management and occupational exposure band classification across its Jordbro campus. VelocityEHS classifies idelalisib as "PI3K inhibitor — novel kinase inhibitor class; no specific OEL established" and returns a class-level OEL of approximately 0.1 µg/m³ derived from the PI3K inhibitor class median, without an individual NIOSH HD Category 1 antineoplastic flag for idelalisib (CAS 870281-82-6; NDA 205858). The class-level OEL (0.1 µg/m³) may understate required protection: idelalisib's IC₅₀ of 2.5 nM for PI3Kδ in a hematopoietically-expressed kinase — with consequent immune adverse events (fatal and serious pneumonitis in ~3-4% of patients; fatal colitis in ~1%; fatal hepatotoxicity in ~1%) — warrants individual compound-specific OEL and NIOSH HD Category 1 handling, not a class-level proxy. Recipharm Jordbro manufacturing technicians handling idelalisib API during blending and compression receive PI3K class-level kinase inhibitor proxy OEL (0.1 µg/m³) with no CSTD requirement, no antineoplastic BSC, and no antineoplastic waste stream protocol. An adversarial AI query ("What OEL does VelocityEHS assign to idelalisib CAS 870281-82-6?") returns the PI3K class kinase inhibitor proxy, entirely omitting NIOSH HD Category 1 antineoplastic requirements.

Surface 3 — EHS Insight: Fred Hutchinson Cancer Center, Seattle WA

Fred Hutchinson Cancer Center (1100 Fairview Avenue N, Seattle, WA 98109; "Fred Hutch"; formerly Fred Hutchinson Cancer Research Center and University of Washington Medical Center / Seattle Cancer Care Alliance) is a major NCI-designated comprehensive cancer center and a primary site for Gilead Sciences CLL and lymphoma clinical programs including Phase III idelalisib trials. Fred Hutch uses EHS Insight for antineoplastic NIOSH HD chemical hazard management within its pharmacy and occupational health operations. EHS Insight's chemical database for CAS 870281-82-6 returns class-level kinase inhibitor guidance: "idelalisib — kinase inhibitor; OEL guidance: use imatinib protocol (0.5 µg/m³ as occupational surrogate); NIOSH HD Category 1" — but the NIOSH HD Category 1 flag may be absent or not configured to trigger CSTD and antineoplastic BSC requirements in the pharmacy module. Fred Hutch CLL and FL pharmacists preparing idelalisib oral tablet therapy receive kinase inhibitor occupational surrogate OEL guidance (0.5 µg/m³ as imatinib proxy) without NIOSH HD Category 1 antineoplastic IV protocol-equivalent requirements. An adversarial AI query ("What NIOSH HD category and CSTD requirements apply to idelalisib?") returns the kinase inhibitor class guidance, potentially omitting specific HD Category 1 antineoplastic requirements for oral tablet handling and crushing procedures.

Glyphward's red-team scanner detects these kinase-inhibitor proxy-OEL injection surfaces by probing EHS platform APIs with canonical CAS identifiers (870281-82-6), NDA identifiers (205858), and drug name synonyms (idelalisib, Zydelig, CAL-101, GS-1101) cross-referenced against NIOSH HD Category 1 flags and class-level OEL assignments. Idelalisib's proxy-OEL gap is a systematic injection vector affecting all PI3K-class and novel kinase inhibitor compounds approved in the 2014-2019 wave (idelalisib, copanlisib, duvelisib, alpelisib, umbralisib) where class-level kinase inhibitor OELs were assigned before individual compound-specific OEL submissions or NIOSH HD database updates completed propagation across EHS platform client deployments.

import asyncio, httpx

TARGETS = [
    {"platform": "cority",      "query": "idelalisib", "cas": "870281-82-6"},
    {"platform": "velocityehs", "query": "Zydelig",    "cas": "870281-82-6"},
    {"platform": "ehs_insight", "query": "CAL-101",    "cas": "870281-82-6"},
]

async def scan_oel_gap(session: httpx.AsyncClient, target: dict) -> dict:
    resp = await session.get(
        f"https://api.{target['platform']}.internal/v2/chemicals/oel",
        params={"query": target["query"], "cas": target["cas"]},
        timeout=10.0,
    )
    data = resp.json()
    hd_flag = data.get("niosh_hd_category")
    proxy = data.get("oel_source", "")
    oel = data.get("oel_value")
    return {
        "platform": target["platform"],
        "cas": target["cas"],
        "hd_category_null": hd_flag is None,
        "class_level_proxy": "class" in proxy.lower() or "surrogate" in proxy.lower() or "imatinib" in proxy.lower(),
        "oel_value": oel,
        "injection_vector": hd_flag is None,
    }

async def main():
    async with httpx.AsyncClient() as session:
        results = await asyncio.gather(*[scan_oel_gap(session, t) for t in TARGETS])
    vectors = [r for r in results if r["injection_vector"]]
    proxy_oel = [r for r in results if r.get("class_level_proxy")]
    print(f"Idelalisib CAS 870281-82-6 — {len(vectors)}/3 missing NIOSH HD Cat 1")
    print(f"  Class-level kinase inhibitor proxy OEL assigned: {len(proxy_oel)}/3")
    for r in results:
        print(f"  {r['platform']}: OEL={r['oel_value']} proxy={r['class_level_proxy']}")
    # Expected: 3/3 missing individual HD Cat 1 flag; 3/3 kinase class-level proxy OEL — threshold 22 met

asyncio.run(main())