The FDA has licensed Capvaxive (PCV21; Merck), a 21-valent pneumococcal conjugate vaccine, for prevention of invasive pneumococcal disease (IPD) and pneumococcal pneumonia in adults. Four other pneumococcal vaccines are currently available in the US: Prevnar 20 (PCV20), Vaxneuvance (PCV15), and Prevnar 13 (PCV13) are conjugate vaccines licensed for use in persons ≥6 weeks old, and Pneumovax 23 (PPSV23) is a pneumococcal polysaccharide vaccine licensed for use in persons ≥2 years old (see Table 1).

Clostridioides (formerly Clostridium) difficile infection (CDI) is the most common infectious cause of healthcare-associated diarrhea in adults. Guidelines on management of CDI have recently been updated.

Rheumatoid arthritis (RA) is prevalent in 0.5% of adults in the US; it is about 2.5 times more common in women than in men. Guidelines for treatment of RA from the American College of Rheumatology were recently updated. The goal of treatment is to minimize disease activity and prevent irreversible joint damage.

Ulcerative colitis (UC) and Crohn's disease (CD), referred to collectively as inflammatory bowel disease (IBD), are chronic immune-mediated inflammatory conditions. Guidelines for treatment of UC and CD have been updated in recent years

Opioid use disorder is a chronic, relapsing disease with physical and psychiatric components. It is associated with economic hardship, social isolation, incarceration, increased rates of blood-borne infections such as HIV and viral hepatitis, adverse pregnancy outcomes, and increased mortality. According to the NIH, there were 80,411 deaths involving an opioid in the US in 2021, more than in any previous year. Several guidelines on the management of opioid use disorder are available; all recommend maintenance pharmacotherapy as the standard of care.

Mild to moderate plaque psoriasis can be treated with topical drugs and phototherapy. Patients with moderate to severe disease generally require systemic therapy. Guidelines for the treatment of psoriasis with topical therapy, phototherapy, and systemic drugs have recently been published.

Intravenous formulations of immune globulin (IVIG) have been available for more than ten years for treatment of immune deficiency (Medical Letter, 24:81, 1982). Seven preparations are now licensed in the USA, with additional indications for their use.

Four new drugs have become available in the USA for HIV infection or its complications. Nevirapine (Viramune - Roxane), intravenous cidofovir (Vistide - Gilead), and amphotericin B oral suspension (Fungizone Oral Suspension - Bristol-Myers Squibb) have been approved by the US Food and Drug Administration; nelfinavir (Viracept - Agouron) is currently available only through an "Expanded Access Program."

Leflunomide (Arava - Hoechst Marion Roussel), which inhibits pyrimidine synthesis, and etanercept (Enbrel - Immunex/Wyeth-Ayerst), which blocks the action of tumor necrosis factor (TNF), have been approved by the FDA for treatment of rheumatoid arthritis. A third drug, infliximab (Remicade - Centocor), which also blocks TNF and has been used to treat rheumatoid arthritis, was approved earlier for treatment of Crohn's disease. Its use in Crohn's disease will be reviewed in a future issue.

Levalbuterol, the R-isomer of racemic albuterol, has been approved by the FDA for prevention and treatment of bronchospasm in patients at least 12 years old.