Sarecycline Review

Non-tuberculous mycobacterial disease: progress and advances in the development of novel candidate and repurposed drugs

Non-tuberculous mycobacteria (NTM) are opportunistic pathogens that can infect all body tissues and organs. In particular, the lungs are the most commonly involved organ, with NTM pulmonary diseases causing serious health issues in patients with underlying lung disease. Moreover, NTM infections have been steadily increasing worldwide in recent years. NTM are also naturally resistant to many antibiotics, specifically anti-tuberculosis (anti-TB) drugs. The lack of drugs targeting NTM infections and the increasing drug resistance of NTM have further made treating these mycobacterial diseases extremely difficult. The currently recommended NTM treatments rely on the extended indications of existing drugs, which underlines the difficulties of new antibiotic discovery against NTM. Another challenge is determining which drug combinations are most effective against NTM infection. To a certain extent, anti-NTM drug development depends on using already available antibiotics and compounds. Here, we aimed to review new antibiotics or compounds with good antibacterial activity against NTM, focusing on their mechanisms of action, in vitro and in vivo antibacterial activities.

Repurposing sarecycline for osteoinductive therapies: an in vitro and ex vivo assessment

INTRODUCTION

Tetracyclines (TCs) embrace a class of broad-spectrum antibiotics with unrelated effects at sub-antimicrobial levels, including an effective anti-inflammatory activity and stimulation of osteogenesis, allowing their repurposing for different clinical applications. Recently, sarecycline (SA)-a new-generation molecule with a narrower antimicrobial spectrum-was clinically approved due to its anti-inflammatory profile and reduced adverse effects verified with prolonged use. Notwithstanding, little is known about its osteogenic potential, previously verified for early generation TCs.

MATERIALS AND METHODS

Accordingly, the present study is focused on the assessment of the response of human bone marrow-derived mesenchymal stromal cells (hBMSCs) to a concentration range of SA, addressing the metabolic activity, morphology and osteoblastic differentiation capability, further detailing the modulation of Wnt, Hedgehog, and Notch signaling pathways. In addition, an ex vivo organotypic bone development system was established in the presence of SA and characterized by microtomographic and histochemical analysis.

RESULTS

hBMSCs cultured with SA presented a significantly increased metabolic activity compared to control, with an indistinguishable cell morphology. Moreover, RUNX2 expression was upregulated 2.5-fold, and ALP expression was increased around sevenfold in the presence of SA. Further, GLI2 expression was significantly upregulated, while HEY1 and HNF1A were downregulated, substantiating Hedgehog and Notch signaling pathways' modulation. The ex vivo model developed in the presence of SA presented a significantly enhanced collagen deposition, extended migration areas of osteogenesis, and an increased bone mineral content, substantiating an increased osteogenic development.

CONCLUSION

Summarizing, SA is a promising candidate for drug repurposing within therapies envisaging the enhancement of bone healing/regeneration.

Development and Research Progress of Anti-Drug Resistant Bacteria Drugs

Bacterial resistance has become increasingly serious because of the widespread use and abuse of antibiotics. In particular, the emergence of multidrug-resistant bacteria has posed a serious threat to human public health and attracted the attention of the World Health Organization (WHO) and the governments of various countries. Therefore, the establishment of measures against bacterial resistance and the discovery of new antibacterial drugs are increasingly urgent to better contain the emergence of bacterial resistance and provide a reference for the development of new antibacterial drugs. In this review, we discuss some antibiotic drugs that have been approved for clinical use and a partial summary of the meaningful research results of anti-drug resistant bacterial drugs in different fields, including the antibiotic drugs approved by the FDA from 2015 to 2020, the potential drugs against drug-resistant bacteria, the new molecules synthesized by chemical modification, combination therapy, drug repurposing, immunotherapy and other therapies.

The Development of Third-Generation Tetracycline Antibiotics and New Perspectives

The tetracycline antibiotic class has acquired new valuable members due to the optimisation of the chemical structure. The first modern tetracycline introduced into therapy was tigecycline, followed by omadacycline, eravacycline, and sarecycline (the third generation). Structural and physicochemical key elements which led to the discovery of modern tetracyclines are approached. Thus, several chemical subgroups are distinguished, such as glycylcyclines, aminomethylcyclines, and fluorocyclines, which have excellent development potential. The antibacterial spectrum comprises several resistant bacteria, including those resistant to old tetracyclines. Sarecycline, a narrow-spectrum tetracycline, is notable for being very effective against Cutinebacterium acnes. The mechanism of antibacterial action from the perspective of the new compound is approached. Several severe bacterial infections are treated with tigecycline, omadacycline, and eravacycline (with parenteral or oral formulations). In addition, sarecycline is very useful in treating acne vulgaris. Tetracyclines also have other non-antibiotic properties that require in-depth studies, such as the anti-inflammatory effect effect of sarecycline. The main side effects of modern tetracyclines are described in accordance with published clinical studies. Undoubtedly, this class of antibiotics continues to arouse the interest of researchers. As a result, new derivatives are developed and studied primarily for the antibiotic effect and other biological effects.

New Acne Therapies and Updates on Use of Spironolactone and Isotretinoin: A Narrative Review

Acne vulgaris is a chronic inflammatory skin disease with a multifactorial pathogenesis. Although a variety of acne treatments are available, limitations of current therapies include tolerability, antimicrobial resistance, and costs and patient burden associated with monitoring. This narrative review focuses on emerging treatments and updates on the management of acne. Clascoterone, sarecycline, trifarotene, and novel lotion formulations of tretinoin and tazarotene have been evaluated in clinical trials and provide new options for treatment. Emerging data on the safety and efficacy of spironolactone and isotretinoin challenge current conventions and suggest a need to reconsider drug monitoring guidelines and risk prevention systems. Additional head-to-head data are needed to confirm these novel treatments' utility in treating acne.

An overview of sarecycline for the treatment of moderate-to-severe acne vulgaris

INTRODUCTION

Sarecycline is a novel, tetracycline-class antibiotic specifically designed to treat inflammatory acne. It offers a narrow spectrum of activity (mainly against Cutinebacterium acnes), and it shows less in vitro activity than other tetracyclines against enteric Gram-negative bacteria, offering advantages over older tetracyclines by decreasing the disruption of the gastrointestinal microbiome and the likelihood of developing bacterial resistance.

AREAS COVERED

The drug's pharmacology, safety profile, and clinical efficacy are discussed. Results of phase I, II and III clinical trials have shown that 1.5 mg/kg/day sarecycline is safe, well tolerated and more effective than placebo in treating inflammatory acne in patients 9 years old and older. Furthermore, sarecycline's narrow spectrum of activity leads to a lower incidence of undesirable off-target antibacterial effects and consequently less adverse events such as diarrhea, fungal overgrowth and vaginal candidiasis.

EXPERT OPINION

Sarecycline could become the first-line antibiotic therapy used in acne in the near future as it is an effective option for treating inflammatory acne lesions. Due to its narrow spectrum of activity, it could have a more adequate safety profile than older tetracyclines; however, head-to-head trials comparing the efficacy and safety profile of sarecycline with other tetracyclines are still needed to prove sarecycline's superiority.