Notes
CRITICAL CLASS CAVEAT: AB-160 (AB160) is NOT a classic covalent ADC. It is a ~160 nm nano-immunoconjugate in which nab-paclitaxel (albumin-bound paclitaxel) nanoparticles are NON-COVALENTLY coated with bevacizumab to target VEGF-A-rich tissue. Consequently there is no chemical linker, no DAR, and no conjugation site (ADCdb lists linker and DAR as 'Undisclosed'; mechanistically they are non-covalent/non-applicable). The "target" (VEGF-A) is a soluble secreted ligand, not a cell-surface antigen. ADCdb cross-refs: DRG0IRZPG, antibody ANI0IZQGT (bevacizumab), target TAR0VKDND (VEGFA), payload PAY0VUPQZ (paclitaxel). Sponsor: Mayo Clinic (investigator-initiated).
TRIAL/OAE STRUCTURE: Phase I NCT02020707 (MC1371), CTCAE v4.0. Total evaluable safety N=21 across THREE cohorts: (1) gynecologic dose-escalation cohort N=10 spanning DL1-DL3 (protocol-allowed ABX 75-175 / BEV 30-70 mg/m2; three DLs tested 125/150/175 ABX); (2) endometrial-expansion N=6 at RP2D/DL2; (3) ovarian-expansion N=5 at RP2D/DL2. RP2D = DL2 (nab-paclitaxel 150 mg/m2 + bevacizumab 60 mg/m2), IV days 1/8/15 q28d; no DLTs. n_rp2d recorded as 21 (total safety-analysis denominator); the RP2D (DL2) disease-specific expansion cohorts total 11 (endometrial 6 + ovarian 5), plus unspecified DL2 escalation patients.
OCULAR (qualifying data): Table 3 ("Grade 2-5 AEs regardless of attribution," which also tabulates the G1 column) lists THREE Grade-1 eye events, EACH at 10% (1/10), ALL confined to the dose-escalation cohort (N=10) and ABSENT from the RP2D endometrial/ovarian expansion cohorts: blurred vision 10%, dry eye 10%, and watering eyes/epiphora 10% (the screen hint missed the third PT). No Grade >=2 ocular event in any cohort -> oae_g3plus_pct=0 (documented). oae_any_pct reported as 10.0 (max across PTs per convention); patient overlap among the 3 ocular PTs is not resolvable, so the true any-ocular incidence is 10-30%. ocular_surface_subtype=Mixed (dry eye + epiphora = ocular surface/lacrimal; blurred vision = visual). Because OAE occurs only in the escalation cohort, ocular rows are tagged line_context to that cohort (N=10), NOT 'RP2D'. Reversibility not reported. These are taxane (free paclitaxel) class effects, NOT auristatin/maytansinoid corneal toxicity.
DOMINANT TOXICITIES (context): hematologic - neutropenia and leukopenia/WBC decrease are the defining Grade 3/4 events (G3+ 50-83% across cohorts; abstract explicitly names neutropenia + leukopenia), anemia universal (100% any-grade, G3 10%). Thromboembolic events were also named as Grade 3/4 in the abstract (Table 3: G3 10% in escalation cohort) but are not captured in toxicity_rows because the organ_system enum has no vascular category. Note: the "44.4% neutropenia / 22.2% leukopenia" figures circulating in secondary summaries are NOT in the primary paper and were not used; per-cohort Table 3 values are reported instead.
PHYSCHEM: paclitaxel = PubChem CID 36314 (MW 853.9; XLogP3 2.5; TPSA 221; formula C47H51NO14; neutral, charge 0). payload_bystander left blank (concept N/A for a non-covalent nanoparticle delivering free paclitaxel). Antibody isotype/origin/Fc (humanized IgG1, wild-type Fc, standard glycosylation) inferred from established bevacizumab identity = tier C.
OTHER: AB160 was also studied in metastatic melanoma under the same MC1371/NCT02020707 program (JCO 2020;38(15_suppl):e22020); the OAE/toxicity data here are from the gynecologic Phase I publication (Kalogera et al., Clin Cancer Res 2024;30(12):2623). First author Eleftheria Kalogera.