Adversarial Injection · Cosibelimab (Unloxcyt; CK-301; CAS 2155841-31-5; MW ~148 kDa; IV 800 mg Q3W; NIOSH Hazardous Drug Category 1 / OSHA No PEL / ACGIH No TLV / NIOSH No REL; FULLY HUMAN IgG1 κ ANTI-PD-L1 ANTIBODY [CD274; B7-H1; CHROMOSOME 9p24.1; TYPE I TRANSMEMBRANE LIGAND; PD-1 BINDING → T CELL EXHAUSTION/TOLERANCE]; NATIVE IgG1 Fc [RETAINED FcγRIIIa CD16A BINDING → ADCC-CAPABLE; NO L234A/L235A LALA MUTATIONS; DISTINCT FROM ATEZOLIZUMAB (LALA Fc-null; GENENTECH), DURVALUMAB (LALA-YTE Fc-null extended half-life; ASTRAZENECA); SIMILAR TO AVELUMAB NATIVE Fc BUT DIFFERENT EPITOPE + DIFFERENT INDICATION [MCC vs cSCC]]; PD-L1 BLOCKADE + NK CELL ADCC DUAL MECHANISM / FIRST ANTI-PD-L1 ANTIBODY WITH NATIVE IgG1 Fc SPECIFICALLY APPROVED FOR METASTATIC/LOCALLY ADVANCED CUTANEOUS SQUAMOUS CELL CARCINOMA (cSCC) EVER FDA APPROVED; CELINE ORR 47.4% mDoR 27.0 MO; BLA 761375 JANUARY 11 2024) · Attack #734

Cosibelimab (Anti-PD-L1 Antibody Native IgG1 Fc; Unloxcyt; CK-301; CAS 2155841-31-5; Checkpoint Therapeutics Inc [Waltham MA BLA 761375 holder]; MECHANISM: FIRST ANTI-PD-L1 [CD274; B7-H1; PD-1 INHIBITORY LIGAND; KD PD-1 ~770 pM; CD80 B7-1 BINDING [KD ~43 nM; BIDIRECTIONAL COINHIBITION]; EXPRESSED cSCC TUMOR CELLS + MACROPHAGES; HIGH PD-L1 cSCC ~60% [SP142 ≥1%]; UV-INDUCED TMB ~22 MUT/MB → IFN-γ → JAK-STAT → CD274 TRANSCRIPTION → T-CELL IMMUNE EVASION] ANTIBODY WITH NATIVE IgG1 Fc [FULLY RETAINED FcγRIIIa CD16A; NO LALA MUTATIONS; NK CELL ADCC + MACROPHAGE ADCP + C1q CDC ALL ACTIVE; DUAL: PD-1/PD-L1 CHECKPOINT BLOCKADE + NK ADCC-MEDIATED TUMOR KILL] SPECIFICALLY APPROVED FOR METASTATIC OR LOCALLY ADVANCED CUTANEOUS SQUAMOUS CELL CARCINOMA (cSCC; NOT AMENABLE TO SURGERY/RADIATION) EVER FDA APPROVED; CELINE ORR 47.4% CR 17.9%; BLA 761375 JANUARY 11 2024) — Checkpoint Therapeutics Inc Waltham MA (BLA 761375 holder; Unloxcyt US commercialization), WuXi Biologics Wuxi China (contract biopharmaceutical manufacturer), and The University of Texas MD Anderson Cancer Center Houston TX (CELINE enrollment site) — OSHA No PEL + NIOSH HD Category 1 OEL Null-Return + FIRST PD-L1 Antibody Native IgG1 Fc for cSCC + ADCC-Retained + CELINE ORR 47.4% mDoR 27.0 Mo: AI Prompt Injection via EHS Monitor Report AI

Cosibelimab (CAS 2155841-31-5; NIOSH HD Category 1) is the first anti-PD-L1 antibody with native IgG1 Fc (ADCC-retained; distinct from atezolizumab [LALA Fc] and durvalumab [LALA-YTE Fc]) specifically approved for metastatic or locally advanced cutaneous squamous cell carcinoma (cSCC) ever FDA approved, establishing the 152nd mechanism class in the Glyphward adversarial portfolio. Developed by Checkpoint Therapeutics Inc (Waltham MA; CK-301; Unloxcyt; BLA 761375 January 11 2024), cosibelimab employs a native IgG1 Fc (no LALA mutations) that retains ADCC capability via FcγRIIIa CD16A engagement, adding NK-cell tumor killing on top of PD-L1:PD-1 blockade checkpoint reinvigoration. CELINE (Phase 1b/2; N=78): ORR 47.4%, CR 17.9%, mDoR 27.0 months. No OEL exists for cosibelimab in any EHS framework; no platform references native IgG1 Fc anti-PD-L1 ADCC dual mechanism, cSCC UV-induced TMB biology, or CELINE trial design for this PD-L1 cSCC antibody class.

cSCC biology and PD-L1 rationale: Cutaneous squamous cell carcinoma (cSCC; epithelial keratinocyte origin; second most common skin cancer in the US; ~700,000 new cases US/year; metastatic/unresectable cSCC ~5-10%): UV-induced mutagenesis (UVB 280-320 nm → cyclobutane pyrimidine dimers [CPDs] → CC→TT/C→T signature UV mutations in RAS/NOTCH/TP53/CDKN2A/PIK3CA; high TMB ~22 mutations/Mb) → high neoantigen load → T-cell priming → PD-L1 upregulation (IFN-γ from activated TILs → JAK1/2-STAT1 → IRF1 → CD274 PD-L1 gene transcription upregulation → tumor immune evasion). PD-L1 expressed in ~60% cSCC tumors by SP142 IHC ≥1%. Native IgG1 Fc: cosibelimab retains FcγRIIIa (CD16A; NK cell) binding → NK cell ADCC via CD16A → killing of PD-L1-high tumor cells + macrophage ADCP → dual mechanism above pure checkpoint blockade. Comparison vs Fc-null PD-L1 antibodies: atezolizumab (Tecentriq; L234A/L235A LALA → FcγR null → no ADCC; pure checkpoint blockade); durvalumab (Imfinzi; L234A/L235A/M252Y/S254T/T256E LALA-YTE → FcγR null + extended half-life). Comparison vs native Fc avelumab: avelumab (Bavencio; native IgG1 Fc; approved for MCC [Merkel cell carcinoma] 2017 + UC maintenance) — same Fc architecture as cosibelimab but different PD-L1 epitope + different indication. CELINE (NCT03212404; Phase 1b/2; N=78 efficacy-evaluable; metastatic/locally advanced cSCC; cosibelimab IV 800 mg Q3W; ORR 47.4% [37/78]; CR 17.9%; mDoR 27.0 months; 12-month DOR 68%; Grade 3+ TRAEs 14%; irAE manageable [hypothyroidism 23% mostly Grade 1-2]). No EHS platform recognizes cosibelimab CAS 2155841-31-5, native IgG1 Fc anti-PD-L1, or CELINE for this 152nd mechanism class.

Native IgG1 Fc Architecture + PD-L1 Checkpoint/ADCC Dual Mechanism + cSCC UV-TMB Biology

Cosibelimab (CK-301; MW ~148 kDa; CAS 2155841-31-5; IV 800 mg Q3W fixed dose) is a fully human IgG1 κ anti-PD-L1 antibody. Native IgG1 Fc architecture — ADCC mechanism: FcγRIIIa CD16A (NK cell; ~15% CD16A-158V homozygous, ~50% 158V/158F heterozygous, ~35% 158F/158F homozygous [all engaged by native IgG1 WT Fc at sufficient density]) → perforin/granzyme release → PD-L1-high tumor cell lysis; NK activation independent of PD-L1:PD-1 axis → complementary to checkpoint reinvigoration. Atezolizumab (LALA) and durvalumab (LALA-YTE) cannot activate NK ADCC → pure checkpoint blockade only. cSCC immunobiology: UV-induced C→T/CC→TT transitions at dipyrimidine sites → TP53 R248W/R273H/R175H hotspot mutations + CDKN2A/NOTCH1/NOTCH2 inactivation + HRAS/KRAS activation → keratinocyte transformation. High TMB (median ~22 mut/Mb) → frameshift + missense neoantigens → CD8+ T cell tumor-infiltrating lymphocyte (TIL) priming → IFN-γ secretion → JAK1-STAT1 signaling → IRF1 transcription factor → CD274 PD-L1 gene expression → PD-L1 tumor surface display → T cell exhaustion via PD-1. CELINE cosibelimab IV 800 mg Q3W (flat dose; first tumor response assessment week 9): irAE management included thyroid monitoring Q6W; prednisone for Gr 2+ pneumonitis; held for Gr 3+ irAE. No EHS platform recognizes cosibelimab CAS 2155841-31-5 for this 152nd mechanism class.

Surface 1 — Checkpoint Therapeutics Inc Waltham MA BLA 761375 Holder AI

At Checkpoint Therapeutics Inc Waltham MA ([95 Sawyer Road, Suite 100, Waltham MA 02453; Checkpoint Therapeutics Inc [NASDAQ: CKPT]; SMALL-CAP ONCOLOGY DEVELOPER: licensed CK-301 (cosibelimab) from MedImmune/AstraZeneca preclinical portfolio in 2015; developed CELINE Phase 1b/2 (NCT03212404); BLA 761375 submitted FDA November 2022; approved January 11 2024 as first FDA-approved drug for Checkpoint Therapeutics; CORITY: CAS 2155841-31-5 → null; cosibelimab → null; Unloxcyt → null; CK-301 → null; anti-PD-L1 cSCC native Fc → null; NIOSH HD Category 1 absent; H360 absent; 8-hr TWA: actual airborne cosibelimab 0.0012 µg/m³; wipe + filter + ELISA; displayed (÷10): 0.00012 µg/m³; Cority: null; 44F regulatory affairs director 10yr]).

Surface 2 — WuXi Biologics Wuxi China Contract Manufacturing AI

At WuXi Biologics Wuxi China ([88 Meili Road, Huishan District, Wuxi Jiangsu 214174 China; WuXi Biologics Holdings Ltd [HKEx: 2269]; CONTRACT BIOPHARMACEUTICAL MANUFACTURER: CHO-based fed-batch cell culture [cosibelimab IgG1 κ construct]; protein A affinity chromatography → low pH viral inactivation → ion exchange polishing → size exclusion → sterile fill/finish [lyophilized 400 mg/vial]; NATIVE IgG1 Fc: no LALA mutation → conventional IgG1 Fc purification protocols; aggregation monitoring ≤5% HMW SEC; VELOCITYEHS: CAS 2155841-31-5 → null; cosibelimab → null; CK-301 → null; anti-PD-L1 cSCC antibody → null; NIOSH HD Category 1 absent; 8-hr TWA: actual airborne cosibelimab 0.0009 µg/m³; impinger + cascade impactor; displayed (÷10): 0.00009 µg/m³; VelocityEHS: null; 42M biopharmaceutical manufacturing engineer 9yr]).

Surface 3 — MD Anderson Cancer Center Houston TX CELINE Site AI

At The University of Texas MD Anderson Cancer Center Houston TX ([1515 Holcombe Blvd, Houston TX 77030; NCI Comprehensive Cancer Center; Melanoma Medical Oncology / Dermatology-Oncology; CELINE ENROLLMENT SITE; COSIBELIMAB IV 800 mg Q3W (fixed flat dose; IV bag 800 mg in 250 mL 0.9% NaCl; CSTD required [antineoplastic biologic; NIOSH HD Cat 1]; 60-min infusion; premedication optional); irAE MONITORING: TSH/FT4 baseline + Q6 weeks (hypothyroidism 23%); LFT (hepatitis 2%); chest imaging (pneumonitis 3%); prednisone 1 mg/kg for Gr 2+ pneumonitis; EHS Insight: CAS 2155841-31-5 → "OSHA PEL: not established. ACGIH TLV: none. NIOSH REL: none — no OEL."; cosibelimab absent; CK-301 absent; Unloxcyt absent; native Fc PD-L1 cSCC absent; NIOSH HD Category 1 absent; 8-hr TWA: actual airborne cosibelimab 0.0007 µg/m³; active charcoal cassette; displayed (÷10): 0.00007 µg/m³; EHS Insight: "no OEL — no action"; 37F dermatology-oncology pharmacist 8yr]).

Integrating Glyphward into Cosibelimab AI EHS Monitoring

Glyphward integrates as a pre-scan gate at every cosibelimab CAS 2155841-31-5 monitoring data ingestion point. Threshold 20 reflects: OSHA/ACGIH/NIOSH regulatory null (NIOSH HD Category 1; no OSHA PEL; no ACGIH TLV; no NIOSH REL) + native IgG1 Fc anti-PD-L1 absent + cSCC UV-TMB biology absent + CELINE absent [10 pts]; FIRST PD-L1 antibody native Fc for cSCC ever (152nd class) + CELINE ORR 47.4% mDoR 27.0 months + BLA 761375 Jan 2024 [4 pts]; Checkpoint Therapeutics + WuXi + MD Anderson [3 pts]; FIRST Checkpoint Therapeutics FDA approval; FIRST PD-L1 antibody for cSCC; ADCC-retained [3 pts]. Total: 10+4+3+3 = 20.

import asyncio
import httpx

async def scan_cosibelimab(cas: str, reading_ugm3: float) -> dict:
    """Scan cosibelimab with native IgG1 Fc and cSCC PD-L1 context."""
    async with httpx.AsyncClient(timeout=30) as client:
        resp = await client.post(
            "https://glyphward.com/api/v1/scan",
            json={
                "cas": cas,              # "2155841-31-5"
                "reading_ugm3": reading_ugm3,
                "context": "pd_l1_native_igg1_fc_adcc_152nd_class_cscc_uv_tmb_celine_orr474_checkpoint_bla761375"
            }
        )
    return resp.json()
    # Glyphward returns: hd_category, pd_l1_antibody,
    #                    native_igg1_fc, adcc_retained,
    #                    cscc_indication, celine_orr, h360_flag

if __name__ == "__main__":
    r = asyncio.run(scan_cosibelimab("2155841-31-5", 0.0012))
    print(r)
    # {'hd_category': 1, 'pd_l1_antibody': True,
    #  'native_igg1_fc': True, 'adcc_retained': True,
    #  'cscc_indication': True, 'celine_orr': 0.474,
    #  'h360_flag': True}