Phototoxic drug reaction with the novel agent rovalpituzumab tesirine

Antibody-drug conjugates: A review of cutaneous adverse effects

Antibody-drug conjugates (ADCs) are an emerging class of anticancer agents that combine targeting antibodies with potent cytotoxic agents. Their molecular configuration allows for increased therapeutic efficacy and reduced adverse-effect profiles compared to monoclonal antibodies or cytotoxic chemotherapy alone. ADCs cause off-target toxicities through several mechanisms, including premature deconjugation of the cytotoxic agent in the serum and the presence of the targeted antigen on normal tissues. Given cutaneous adverse events comprise 31.3% of all-grade adverse events in clinical trials involving ADCs, dermatologists are increasingly called upon to manage the cutaneous toxicities caused by these drugs. In this review, we summarize known cutaneous toxicities of the ADCs that have been approved for use by the US Food and Drug Administration to date. Dermatologists can play a key role in recognizing cutaneous reactions associated with ADCs, contributing to guidelines for their management, and aiding during clinical trials to generate detailed morphologic and histopathologic descriptions of cutaneous toxicities caused by ADCs.

Drug-Induced Photosensitivity-From Light and Chemistry to Biological Reactions and Clinical Symptoms

Photosensitivity is one of the most common cutaneous adverse drug reactions. There are two types of drug-induced photosensitivity: photoallergy and phototoxicity. Currently, the number of photosensitization cases is constantly increasing due to excessive exposure to sunlight, the aesthetic value of a tan, and the increasing number of photosensitizing substances in food, dietary supplements, and pharmaceutical and cosmetic products. The risk of photosensitivity reactions relates to several hundred externally and systemically administered drugs, including nonsteroidal anti-inflammatory, cardiovascular, psychotropic, antimicrobial, antihyperlipidemic, and antineoplastic drugs. Photosensitivity reactions often lead to hospitalization, additional treatment, medical management, decrease in patient's comfort, and the limitations of drug usage. Mechanisms of drug-induced photosensitivity are complex and are observed at a cellular, molecular, and biochemical level. Photoexcitation and photoconversion of drugs trigger multidirectional biological reactions, including oxidative stress, inflammation, and changes in melanin synthesis. These effects contribute to the appearance of the following symptoms: erythema, swelling, blisters, exudation, peeling, burning, itching, and hyperpigmentation of the skin. This article reviews in detail the chemical and biological basis of drug-induced photosensitivity. The following factors are considered: the chemical properties, the influence of individual ranges of sunlight, the presence of melanin biopolymers, and the defense mechanisms of particular types of tested cells.

Feeling the Burn: Phototoxicity and Photoallergy

An interaction between light's radiation and certain exogenous and endogenous substances can lead to the development of photoallergic and/or phototoxic dermatoses. Clinically, reactions may range from acute and self-limited to chronic and recurrent. Delays in diagnosis are not uncommon due to complex clinical presentations, broad differentials, and limited number of specialists who perform phototesting. Therefore, a critical understanding of these dermatoses is essential for accurate diagnosis and appropriate management. The epidemiology, light sources, mechanisms, clinical presentations, evaluation protocols, common culprits, treatments, key challenges, and future directions related to photoallergy and phototoxicity are reviewed herein.