Topical sirolimus for the treatment of cutaneous manifestations of vascular anomalies: A case series

Recent advances in nanomaterial-driven strategies for diagnosis and therapy of vascular anomalies

Nanotechnology has demonstrated immense potential in various fields, especially in biomedical field. Among these domains, the development of nanotechnology for diagnosing and treating vascular anomalies has garnered significant attention. Vascular anomalies refer to structural and functional anomalies within the vascular system, which can result in conditions such as vascular malformations and tumors. These anomalies can significantly impact the quality of life of patients and pose significant health concerns. Nanoscale contrast agents have been developed for targeted imaging of blood vessels, enabling more precise identification and characterization of vascular anomalies. These contrast agents can be designed to bind specifically to abnormal blood vessels, providing healthcare professionals with a clearer view of the affected areas. More importantly, nanotechnology also offers promising solutions for targeted therapeutic interventions. Nanoparticles can be engineered to deliver drugs directly to the site of vascular anomalies, maximizing therapeutic effects while minimizing side effects on healthy tissues. Meanwhile, by incorporating functional components into nanoparticles, such as photosensitizers, nanotechnology enables innovative treatment modalities such as photothermal therapy and photodynamic therapy. This review focuses on the applications and potential of nanotechnology in the imaging and therapy of vascular anomalies, as well as discusses the present challenges and future directions.

Medical Therapeutics for the Treatment of Vascular Anomalies: Part 3

The discovery of inherited and somatic genetic mutations, along with advancements in clinical and scientific research, has improved the understanding of vascular anomalies and changed the treatment paradigm. With the aim of minimizing the need for invasive procedures and improving disease outcomes, molecularly targeted medications and anti-angiogenesis agents have become important as both adjuncts to surgery, and increasingly, as the primary treatment of vascular anomalies. This article highlights the commonly used and emerging therapeutic medications for nonmalignant vascular tumors and vascular malformations.

Verification of the efficacy of topical sirolimus gel for systemic rare vascular malformations: a pilot study

Numerous clinical trials of sirolimus, an inhibitor of mechanistic/mammalian target of rapamycin complex 1, for the treatment of vascular malformations have been conducted. However, aside from lymphatic malformations, the efficacy of sirolimus for venous and capillary malformations has not been established. Moreover, no generalized venous or capillary malformations have been treated with topical sirolimus. To evaluate the safety and efficacy of topical sirolimus for venous and capillary malformations and to compare the efficacy of topical and systemic sirolimus therapy, an open-label single-arm pilot study with 0.2% sirolimus gel was conducted from July 19, 2019, to January 30, 2020, in four patients diagnosed with different vascular malformations (blue rubber bleb nevus syndrome, common venous malformation, phakomatosis pigmentovascularis type IVb, and angiokeratoma in Fabry disease). The primary endpoint was the safety evaluation of sirolimus gel. The main secondary endpoint was the improvement rate evaluated by the Central Judgment Committee at 12 weeks using photographs. No adverse events were observed. Blood sirolimus was not detected in any patient. Two patients (50%) had mild improvement, and the remaining two patients (50%) showed no change after 12 weeks of treatment. Blue rubber bleb nevus syndrome, a generalized venous malformation, showed the greatest response. In conclusion, 0.2% sirolimus gel was found to be as clinically effective as systemic sirolimus treatment in patients with venous and capillary malformations and more effective for early active lesions, even systemic venous malformations.

Vascular malformations: An overview of their molecular pathways, detection of mutational profiles and subsequent targets for drug therapy

Vascular malformations are anomalies in vascular development that portend a significant risk of hemorrhage, morbidity and mortality. Conventional treatments with surgery, radiosurgery and/or endovascular approaches are often insufficient for cure, thereby presenting an ongoing challenge for physicians and their patients. In the last two decades, we have learned that each type of vascular malformation harbors inherited germline and somatic mutations in two well-known cellular pathways that are also implicated in cancer biology: the PI3K/AKT/mTOR and RAS/RAF/MEK pathways. This knowledge has led to recent efforts in: (1) identifying reliable mechanisms to detect a patient's mutational burden in a minimally-invasive manner, and then (2) understand how cancer drugs that target these mutations can be repurposed for vascular malformation care. The idea of precision medicine for vascular pathologies is growing in potential and will be critical in expanding the clinician's therapeutic armamentarium.

Congenital vascular lesions, could MAPK and PI3K inhibitors pave the way to new therapies?

PURPOSE OF REVIEW

Superficial vascular anomalies are a heterogeneous group of malformative and tumoral lesions, developed from various types of abnormal lymphatic and/or blood vessels. They are mostly benign but their clinical evolution can lead to dramatic cosmetic concern, functional impairment and even life-threatening conditions. Until recently, treatments relied on invasive procedures such as embotherapy/sclerotherapy and/or surgery. Recent molecular findings pave the way of new medical therapies.

RECENT FINDINGS

Two main signaling pathways PI3K-AKT-mTOR and RAS-MAPK-ERK are now identified to encounter for the causative pathogenic genetic variants of most vascular anomalies. Involved genes are also responsible for several common neoplasms for which targeted therapies are already available or under development. Repurposing treatment strategy is considered for vascular anomalies treatment with promising results.

SUMMARY

The mTOR inhibitor sirolimus is the most used targeted therapy so far but new molecules are tested currently.

Topical sirolimus: Difference between compounded preparations and commercial oral solution

Topical sirolimus has become a crucial treatment option for many dermatologic disorders. Because an FDA-approved topical formulation is not commercially available, sirolimus creams, ointments, and gels are professionally prepared by compounding pharmacies. Also, the topical use of a commercially available sirolimus solution approved for oral administration is described regularly. To better guide providers in their decision-making when topical sirolimus is being considered, this article highlights the substantial pharmaceutical and clinical differences between commercial oral solution and compounded preparations specifically designed for topical therapy.

Genetic Basis and Therapies for Vascular Anomalies

Vascular and lymphatic malformations represent a challenge for clinicians. The identification of inherited and somatic mutations in important signaling pathways, including the PI3K (phosphoinositide 3-kinase)/AKT (protein kinase B)/mTOR (mammalian target of rapamycin), RAS (rat sarcoma)/RAF (rapidly accelerated fibrosarcoma)/MEK (mitogen-activated protein kinase kinase)/ERK (extracellular signal-regulated kinases), HGF (hepatocyte growth factor)/c-Met (hepatocyte growth factor receptor), and VEGF (vascular endothelial growth factor) A/VEGFR (vascular endothelial growth factor receptor) 2 cascades has led to the evaluation of tailored strategies with preexisting cancer drugs that interfere with these signaling pathways. The era of theranostics has started for the treatment of vascular anomalies. Registration: URL: https://www.clinicaltrialsregister.eu; Unique identifier: 2015-001703-32.