The FDA has approved Rebyota (Ferring), a rectally-administered, live fecal microbiota suspension, for prevention of additional recurrences of Clostridioides difficile infection (CDI) following antibiotic treatment for a recurrent episode of CDI in adults. Rebyota is the first microbiome-based treatment to be approved for this indication. It is not approved for initial treatment of CDI. Fecal microbiota transplantation (FMT) has been used in patients with multiple CDI recurrences.

The FDA has approved valbenazine (Ingrezza – Neurocrine Biosciences), a vesicular monoamine transporter 2 (VMAT2) inhibitor, for treatment of tardive dyskinesia in adults. It is the first drug to be approved in the US for this indication; two other VMAT2 inhibitors, tetrabenazine (Xenazine, and generics) and deutetrabenazine (Austedo), were approved earlier for treatment of chorea associated with Huntington's disease.

The FDA has approved erenumab-aooe (Aimovig – Amgen/Novartis), a once-monthly, subcutaneously-injected, monoclonal antibody against the calcitonin gene-related peptide receptor, for preventive treatment of migraine in adults. It is the first drug in its class to be approved by the FDA.

Methicillin-resistant Staphylococcus aureus (MRSA), which was traditionally a nosocomially-acquired organism but now frequently occurs in the absence of healthcare exposure, is the predominant cause of suppurative skin and soft-tissue infections in many parts of the US. Community-associated MRSA usually causes furunculosis, purulent cellulitis, and abscesses, but necrotizing fasciitis, necrotizing pneumonia, and sepsis can also occur.

The FDA has approved Vowst (Seres Therapeutics/Nestle HealthScience), an oral capsule containing live fecal microbiota spores, for prevention of additional recurrences of Clostridioides difficile infection (CDI) in adults. Vowst is the first orally administered microbiota-based treatment to be approved for this indication. A rectally-administered live fecal microbiota-based suspension (Rebyota) was approved in 2022 for the same indication. Neither product is approved for acute treatment of CDI.

The FDA has licensed MenQuadfi (Sanofi Pasteur), a quadrivalent polysaccharide conjugate vaccine that uses tetanus toxoid as a protein carrier, for prevention of invasive meningococcal disease caused by Neisseria meningitidis serogroups A, C, W, and Y (MenACWY) in persons ≥2 years old.

The gram-positive anaerobic bacillus Clostridium difficile is the most common identifiable cause of antibiotic-associated diarrhea. The antibiotics most often implicated have been ampicillin, second and third generation cephalosporins, clindamycin and fluoroquinolones. The emergence in recent years of a new, more toxic epidemic strain (BI/NAP1), possibly related to widespread use of fluoroquinolones, has caused a marked increase in the incidence and severity of C. difficile-associated disease (CDAD).

The FDA has approved two subcutaneously injected calcitonin gene-related peptide (CGRP) antagonists, fremanezumab-vfrm (Ajovy – Teva) and galcanezumab-gnlm (Emgality – Lilly), for migraine prevention in adults. Fremanezumab and galcanezumab are the second and third subcutaneously injected monoclonal antibodies that target the CGRP pathway to be approved by the FDA for this indication; erenumab-aooe (Aimovig), which targets the CGRP receptor, was the first.

The FDA has approved vancomycin oral solution (Firvanq – Cutis Pharma) for treatment of Clostridium difficile-associated diarrhea and enterocolitis caused by Staphylococcus aureus, including methicillin-resistant strains (MRSA).

Probiotics are live, nonpathogenic microorganisms (usually bacteria or yeasts) marketed as dietary supplements. They have not been approved by the FDA for any indication. Since our last article on this subject, some new data have become available.