Hidradenitis suppurativa (HS) is a painful, chronic inflammatory condition that forms recurring nodules and abscesses in skin folds, leading to severe scarring. While the exact pathogenesis is still being determined, it is thought to involve follicular occlusion and rupture, driven by multifactorial influences such as genetics, environment, hormones, microbiome, and immune dysregulation. The complex nature of this disease entails complicated management and has led to the development of various therapies targeting these different factors. While moderate-to-severe HS has seen growing therapeutic options in recent years, mild early-stage forms of the disease lack any approved treatments. This review examines the most recent developments in topical therapies specifically for mild HS, along with advancements in daily HS skin care and post de-roofing wound management. These emerging therapies offer the potential for more effective, personalized care to reduce the disease burden for patients living with HS.

Chronic hand dermatitis (CHD), also referred to as chronic hand eczema, is a persistent inflammatory skin disorder characterized by erythema, fissuring, scaling, lichenification, and significant pruritus and pain. The condition is often debilitating, particularly because the hands are constantly exposed to mechanical friction, detergents, irritants, and environmental stressors. Traditional treatments such as topical corticosteroids, calcineurin inhibitors, phototherapy, and systemic immunomodulators are limited by safety concerns, incomplete efficacy, or poor long-term tolerability. Delgocitinib 2% cream, a non-steroidal, topical pan-Janus kinase (JAK) inhibitor, represents the first targeted therapy specifically approved for moderate-to-severe CHD in adults. Through inhibition of JAK1, JAK2, JAK3, and tyrosine kinase 2, delgocitinib broadly suppresses multiple cytokine pathways involved in hand eczema pathogenesis. Clinical trials have demonstrated significant improvement in Investigator's Global Assessment scores, Hand Eczema Severity Index, pruritus, pain, and quality of life, along with sustained benefit in long-term extension studies. Safety data reveal minimal systemic absorption, no steroid-associated skin atrophy, and a favorable tolerability profile without box warnings. This review examines the pathophysiology of CHD and the clinical evidence supporting delgocitinib as an effective, steroid-sparing therapeutic option.

The skin's role as a mirror of internal disease has long been established, with clear associations to several internal organs. However, its relationship with bone is less well known. There are clear physiological links between the two organ systems, with their shared factors crucial to maintain structural integrity and homeostasis. Collagen, vitamin D homeostasis, aging, medications, and the gut microbiome are all factors that impact both skin and bone. It is of utmost importance that the skin-bone axis be adequately understood to support a healthy aging process. In this review, we discuss the multiple facets related to skin and bone health, their interconnectivity, as well as the importance of promoting whole body health.

Exosomes are nanosized extracellular vesicles increasingly recognized as regulators of cutaneous biology with direct clinical relevance. In dermatology, they influence keratinocyte and fibroblast proliferation, pigmentation pathways, and immune modulation in disorders such as atopic dermatitis and cutaneous lupus. Their strongest evidence lies in wound healing, where exosomes accelerate closure by dampening proinflammatory cytokines (tumor necrosis factor-α, interleukin-6, matrix metalloproteinase-9), enhancing angiogenesis through vascular endothelial growth factor signaling, and improving collagen deposition and scar quality. Early studies also support their role in regenerative skin care, including reversal of photoaging, improved elasticity, and stimulation of hair follicle growth. Although current use is limited to cosmetic applications without United States Food and Drug Administration (FDA) approval, international experience suggests therapeutic potential in chronic wounds, inflammatory dermatoses, and pigmentation disorders. For clinicians, exosomes represent a novel biologic platform that may soon complement established therapies, underscoring the importance of ongoing translational research and regulatory clarity.

Zasocitinib is a novel highly selective tyrosine kinase 2 (TYK2) inhibitor that is in late phase development for the treatment of psoriasis and psoriatic arthritis. This article will review its efficacy, safety and tolerability. Currently, deucravacitinib is the only TYK2 inhibitor with regulatory approval from most major authorities. Zasocitinib offers potential benefits, as it has higher target selectivity and affinity of the Janus homology 2 (JH2) domain of TYK2 as compared to deucravacitinib. This selectivity leads to minimal inhibition of Janus kinase (JAK) 1, JAK2 and JAK3 (JAK1-3), and therefore may result in less off-target effects that have been associated with other molecules.

Hyperhidrosis (HH), a condition characterized by excessive sweating beyond thermoregulation, significantly impairs quality of life. Conventional medications to treat HH include aluminum chloride hexahydrate, systemic anticholinergics, and botulinum toxin injections. New treatments have emerged including glycopyrronium bromide, sofpironium bromide, targeted alkali thermolysis, and microwave devices. This paper reviews the mechanism of action, efficacy, safety, and practical considerations associated with these treatments.

Hidradenitis suppurativa (HS) is a chronic, recurrent inflammatory skin disease characterized by painful nodules, abscesses, sinus tracts, and scarring, with significant impact on quality of life. Although biologics have expanded treatment options for moderate to severe disease, there are currently no approved therapies specifically indicated for mild HS. Emerging evidence implicates dysregulation of the Janus kinase-signal transducer and activator of transcription (JAK-STAT) pathway in HS pathophysiology, suggesting JAK inhibition as a promising therapeutic strategy. This review summarizes current evidence on JAK inhibition in HS, with a focus on topical ruxolitinib. Early clinical trials in patients with mild to moderate HS have demonstrated encouraging efficacy, including significant improvements in Hidradenitis Suppurativa Clinical Response (HiSCR) rates and histologic reductions in epidermal and dermal inflammation, alongside a favorable safety profile. Existing data support topical ruxolitinib as a promising, targeted, and potentially safer treatment option for early-stage HS.

Biologics have emerged in recent years as relatively safe and effective options for managing plaque psoriasis, however, a subset of patients remain reluctant to initiate biologic therapy. Icotrokinra is a novel, first-in-class oral peptide that targets the interleukin-23 receptor and has demonstrated a favorable safety and efficacy profile comparable to that of injectable biologics in individuals aged 12 years and older. This review summarizes the clinical trial data regarding the safety and efficacy of icotrokinra.

Alopecia areata (AA), an autoimmune condition characterized by non-scarring hair loss, affects 2% of the United States population. AA is a CD8 T-cell driven autoimmune disease in which the cytokines interferon-gamma and interleukin-15 play a central role in disease progression. These pathways depend on Janus kinase (JAK) signaling, making JAK inhibitors an ideal therapeutic option in treating AA. Deuruxolitinib, an oral JAK inhibitor, was approved by the US Food and Drug Administration in July 2024, for the treatment of severe AA in adults. Deuruxolitinib is the third oral JAK inhibitor approved for the treatment of severe AA, the others being baricitinib and ritlecitinib. Deuruxolitinib's mechanism of action, clinical efficacy, and safety profile in the treatment of AA are reviewed.

Immunotherapy has shown promise in treating locally advanced, recurrent, and metastatic cutaneous squamous cell carcinoma. More recently, studies have shown the role of immunotherapy as neoadjuvant treatment in advanced disease for which surgery may not be curative or would be expected to result in functional or cosmetic morbidity. This paper reviews data showing the safety and efficacy of cemiplimab as neoadjuvant treatment in cutaneous squamous cell carcinoma. Early findings suggest that neoadjuvant immunotherapy may help improve surgical outcomes by reducing tumor burden before resection.

Atopic dermatitis (AD) is a common, chronic immune-mediated inflammatory skin disease. The OX40-OX40 ligand (OX40L) pathway has emerged as a novel therapeutic target. On this basis, three phase II clinical trials have been conducted to evaluate the efficacy and safety of three different OX40-OX40L inhibitors (amlitelimab, rocatinlimab, and telazorlimab) in moderate-to-severe AD. Herein, we review the published data from these studies.

Atopic dermatitis (AD) is a common inflammatory skin condition characterized by erythema and intense pruritus. A key pathway implicated in its pathogenesis is the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) signaling pathway. Upadacitinib, a JAK inhibitor, has been approved for the treatment of moderate-to-severe AD. This review evaluates the long-term safety and efficacy of upadacitinib in AD, incorporating findings from the Measure Up 1 and Measure Up 2 phase 3 studies.

Neurofibromatosis type 1 (NF1) is a genetic condition inherited in an autosomal dominant pattern, but with 50% of cases caused by de novo mutations. Neurofibromin, the gene product in NF1, regulates the RAS/MAPK pathway, and mutation can lead to cell proliferation and the development of tumours. NF1 often presents in childhood with cafe-au-lait macules, skinfold freckling, nervous system tumours, and phenotypically variable findings. Plexiform neurofibromas (PN), a type of peripheral nerve sheath tumour seen in NF1, are typically histologically benign. However, PN can cause significant physical disfigurement, pain, and decreased quality of life, and have historically been difficult to treat. Selumetinib, a MEK inhibitor inhibiting the RAS/MAPK pathway, was Health Canada approved in 2022 for the treatment of symptomatic, inoperable PN in individuals with NF1 aged 2 years and older. Phase 1 and 2 trials have demonstrated reduced tumour size, decreased disfigurement and pain, and increased quality of life.