Trastuzumab botidotin

The 'Antibodies to Watch' article series provides an annual summary of commercially sponsored monoclonal antibody therapeutics currently in late-stage clinical development, regulatory review, and those recently granted a first approval in any country. In this installment, we discuss key details for 16 antibody therapeutics granted a first approval in 2023, as of November 17 (lecanemab (Leqembi), rozanolixizumab (RYSTIGGO), pozelimab (VEOPOZ), mirikizumab (Omvoh), talquetamab (Talvey), elranatamab (Elrexfio), epcoritamab (EPKINLY), glofitamab (COLUMVI), retifanlimab (Zynyz), concizumab (Alhemo), lebrikizumab (EBGLYSS), tafolecimab (SINTBILO), narlumosbart (Jinlitai), zuberitamab (Enrexib), adebrelimab (Arelili), and divozilimab (Ivlizi)). We briefly review 26 product candidates for which marketing applications are under consideration in at least one country or region, and 23 investigational antibody therapeutics that are forecast to enter regulatory review by the end of 2024 based on company disclosures. These nearly 50 product candidates include numerous innovative bispecific antibodies, such as odronextamab, ivonescimab, linvoseltamab, zenocutuzumab, and erfonrilimab, and antibody-drug conjugates, such as trastuzumab botidotin, patritumab deruxtecan, datopotamab deruxtecan, and MRG002, as well as a mixture of two immunocytokines (bifikafusp alfa and onfekafusp alfa). We also discuss clinical phase transition and overall approval success rates for antibody therapeutics, which are crucial to the biopharmaceutical industry because these rates inform decisions about resource allocation. Our analyses indicate that these molecules have approval success rates in the range of 14-32%, with higher rates associated with antibodies developed for non-cancer indications. Overall, our data suggest that antibody therapeutic development efforts by the biopharmaceutical industry are robust and increasingly successful.

To report 3 cases of reversible epitheliopathy induced by A166-a human epidermal growth factor receptor (HER2)-targeted antibody-drug conjugate (ADC) therapy for resistant HER2 tumours.

Advanced HER2 tumour patients were enrolled in A166 phase I/II clinical trial using Bayesian logistic regression model dose escalation. Key exclusion criteria were ≥grade 2 (G2) corneal pathology, severe organ disease, and other cancer therapy within 4 weeks. Eye exams were performed at baseline, regularly scheduled intervals, and additionally upon A166-induced ocular symptoms. Topical therapy with autologous serum tears (ASTs) was implemented based on visual acuity, symptoms, and slit lamp exam. A166 was withheld if ≥G2 ocular toxicity developed; if status improved to ≤G1, A166 therapy was resumed. Visual acuity, corneal exam, and subjective comfort were recorded.

After ≥2 cycles of A166, 6 eyes of 3/23 enrolled patients developed whorl pattern epitheliopathy suggestive of limbal stem cell (LSC) dysfunction requiring cessation of A166 despite positive tumour response. Patients 1 and 3 received 3.6 mg/kg A166 dose, and patient 2 received 3.0 mg/kg. Topical steroids (2/4 eyes) failed to improve epitheliopathy. Adding ASTs improved vision, ocular comfort, and whorl pattern epitheliopathy in 6/6 eyes within 3 weeks. Patient 1 continues to improve on ASTs; patient 2 withdrew from the study; and patient 3 resumed A166 therapy.

A166 precipitates LSC dysfunction-like epitheliopathy. Combination therapy including aggressive lubrication, withholding drug, and ASTs help reverse toxicity. Recognizing that ADC-induced epitheliopathy can respond to ocular management may enable cancer patients to continue lifesaving therapy.