Treatment-induced and Pre-existing Anti-peg Antibodies: Prevalence, Clinical Implications, and Future Perspectives

Impact of Anti-PEG IgM Induced via the Topical Application of a Cosmetic Product Containing PEG Derivatives on the Antitumor Effects of PEGylated Liposomal Antitumor Drug Formulations in Mice

Poly(ethylene glycol) (PEG) is used in many common products, such as cosmetics. PEG, however, is also used to covalently conjugate drug molecules, proteins, or nanocarriers, which is termed PEGylation, to serve as a shield against the natural immune system of the human body. Repeated administration of some PEGylated products, however, is known to induce anti-PEG antibodies. In addition, preexisting anti-PEG antibodies are now being detected in healthy individuals who have never received PEGylated therapeutics. Both treatment-induced and preexisting anti-PEG antibodies alter the pharmacokinetic properties, which can result in a subsequent reduction in the therapeutic efficacy of administered PEGylated therapeutics through the so-called accelerated blood clearance (ABC) phenomenon. Moreover, these anti-PEG antibodies are widely reported to be related to severe hypersensitivity reactions following the administration of PEGylated therapeutics, including COVID-19 vaccines. We recently reported that the topical application of a cosmetic product containing PEG derivatives induced anti-PEG immunoglobulin M (IgM) in a mouse model. Our finding indicates that the PEG derivatives in cosmetic products could be a major cause of the preexistence of anti-PEG antibodies in healthy individuals. In this study, therefore, the pharmacokinetics and therapeutic effects of Doxil (doxorubicin hydrochloride-loaded PEGylated liposomes) and oxaliplatin-loaded PEGylated liposomes (Liposomal l-OHP) were studied in mice. The anti-PEG IgM antibodies induced by the topical application of cosmetic products obviously accelerated the blood clearance of both PEGylated liposomal formulations. Moreover, in C26 tumor-bearing mice, the tumor growth suppressive effects of both Doxil and Liposomal l-OHP were significantly attenuated in the presence of anti-PEG IgM antibodies induced by the topical application of cosmetic products. These results confirm that the topical application of a cosmetic product containing PEG derivatives could produce preexisting anti-PEG antibodies that then affect the therapeutic efficacy of subsequent doses of PEGylated therapeutics.

Harnessing Biomaterials for Safeguarding Chimeric Antigen Receptor T Cell Therapy: An Artful Expedition in Mitigating Adverse Effects

Chimeric antigen receptor T cell (CAR-T) therapy has emerged as a groundbreaking approach in cancer treatment, showcasing remarkable efficacy. However, the formidable challenge lies in taming the formidable side effects associated with this innovative therapy, among which cytokine release syndrome (CRS), immune effector cell-associated neurotoxicity syndrome (ICANS) and on-target off-tumor toxicities (OTOT) are typical representatives. Championing the next frontier in cellular immunotherapy, this comprehensive review embarks on an artistic exploration of leveraging biomaterials to meticulously navigate the intricate landscape of CAR-T cell therapy. Unraveling the tapestry of potential toxicities, our discourse unveils a symphony of innovative strategies designed to elevate the safety profile of this revolutionary therapeutic approach. Through the lens of advanced medical science, we illuminate the promise of biomaterial interventions in sculpting a safer and more efficacious path for CAR-T cell therapy, transcending the boundaries of conventional treatment paradigms.

Retinal Vasculitis After Intravitreal Pegcetacoplan: Report From the ASRS Research and Safety in Therapeutics (ReST) Committee

Purpose: To analyze post-marketing cases of retinal vasculitis after intravitreal pegcetacoplan. Methods: The American Society of Retina Specialists (ASRS) Research and Safety in Therapeutics (ReST) Committee as well as an expert panel performed a retrospective review of cases of retinal vasculitis reported to the ASRS. Clinical and imaging characteristics were reviewed for evidence of retinal vasculitis and analyzed. Results: Fourteen eyes of 13 patients were confirmed to have retinal vasculitis by review of imaging studies. All cases occurred after the first pegcetacoplan injection. Occlusive retinal vasculopathy was confirmed in 11 eyes (79%). Patients presented a median of 10.5 days (range, 8-23 days) after pegcetacoplan injection. All eyes had anterior chamber inflammation, and 12 eyes (86%) had vitritis. Vasculopathy involved retinal veins (100%) more than arteries (73%), and 12 eyes (86%) had retinal hemorrhages. The median visual acuity (VA) was 20/60 (range, 20/30-5/200) at baseline, 20/300 (range, 20/100-no light perception [NLP]) at vasculitis presentation, and 20/200 (range 20/70-NLP) at the last follow-up. Eight eyes (57%) had more than a 3-line decrease in VA, and 6 eyes (43%) had more than a 6-line decrease in VA from baseline to the final follow-up, including 2 eyes that were enucleated. Six eyes (43%) developed signs of anterior segment neovascularization. Conclusions: There is currently no known etiology for vasculitis in this series. Optimum treatment strategies remain unknown. Infectious etiologies should be considered, and corticosteroid treatments may hasten resolution of inflammatory findings. Continued treatment of affected patients with pegcetacoplan should be avoided.