Key Infectious Disease Updates: C. difficile, Salmonella Outbreak, Hepatitis C Treatment, and More
Key Insights
Mayo Clinic Arizona found removing _C. difficile_ from gastrointestinal pathogen panels reduced unnecessary treatments and improved diagnostic stewardship.
A _Salmonella (search)_ outbreak linked to cucumbers has sickened 68 people across 19 US states, leading to a product recall by SunFed Produce LLC.
Atea Pharmaceuticals' combination therapy for hepatitis C (search) achieved a 98% SVR12 rate in a Phase 2 trial, paving the way for Phase 3 studies.
Diagnostic Stewardship Reduces Unnecessary C. difficile Treatments
A study at Mayo Clinic Arizona demonstrated that removing Clostridioides difficile (search) from gastrointestinal pathogen panels (GIPP) led to a reduction in unnecessary treatments and improved diagnostic stewardship without delaying diagnoses. Before the intervention, C. difficile was detected in over half of GIPP tests, often leading to unnecessary treatment. After removing C. difficile from the panel, GIPP orders decreased by 17%, and prescriptions for C. difficile treatment significantly dropped. The intervention encouraged more targeted testing (toxin-first with PCR) rather than relying on broad panels, which reduced treatment of incidental colonization.
Salmonella Outbreak Linked to Cucumbers
A Salmonella (search) outbreak linked to cucumbers has sickened 68 people across 19 US states, with 18 hospitalizations reported. The outbreak has been traced to cucumbers grown by Agrotato in Sonora, Mexico, and distributed by SunFed Produce LLC, which recalled the affected products on November 27, 2024. The CDC advises consumers to check for "SunFed Mexico" stickers on cucumbers and discard or return any affected products, particularly those purchased between October 12 and November 26. Symptoms of Salmonella infection include diarrhea, abdominal cramps, fever, and nausea.
Atea Pharmaceuticals' Hepatitis C Combination Therapy Shows Promise
Atea Pharmaceuticals announced that its investigational combination therapy for hepatitis C (search) (HCV), consisting of bemnifosbuvir and ruzasvir, met the primary endpoint in a Phase 2 trial, achieving a 98% sustained virologic response (SVR12) at 12 weeks post-treatment after just 8 weeks of therapy. This promising result was observed in non-cirrhotic patients infected with HCV genotypes 1-4, with 99% of adherent patients achieving SVR12. In cirrhotic patients, the SVR12 rate was 88%. The therapy demonstrated robust pan-genotypic potency, favorable safety profiles, and minimal drug-drug interaction risks. Atea plans to initiate a Phase 3 trial in early 2025, aiming to enhance patient convenience with a fixed-dose combination tablet and to further assess efficacy, particularly in cirrhotic patients with a longer treatment duration.
Gilead's Lenacapavir Demonstrates High Efficacy in HIV Prevention
During its two Phase 3 clinical trials, Gilead's twice-yearly lenacapavir injection demonstrated high efficacy in preventing HIV (search) infection. In the PURPOSE 1 trial, lenacapavir showed 100% efficacy in preventing HIV in cisgender women, with zero infections observed in the treatment group. The PURPOSE 2 trial, which included a broader, geographically diverse population, showed 99.9% efficacy with only two infections in the lenacapavir group, a 96% reduction in HIV infections compared to background HIV incidence (bHIV). Lenacapavir was superior to both bHIV and the standard once-daily oral PrEP (Truvada), prompting the independent Data Monitoring Committee to stop the blinded phase of both trials due to the compelling results. Both lenacapavir and Truvada were well-tolerated, with no significant safety concerns. Gilead has now submitted a New Drug Application (NDA) for lenacapavir for HIV pre-exposure prophylaxis (PrEP) and is working on expanding access globally, especially in areas of high need.