Cannabis-based products show limited short-term benefit for chronic pain, with increased risk of adverse effects

Embargoed for release until 5:00 p.m. ET on Monday 22 December 2025   

Follow @Annalsofim on X, Facebook, Instagram, Bluesky, and Linkedin             
Below please find summaries of new articles that will be published in the next issue of Annals of Internal Medicine. The summaries are not intended to substitute for the full articles as a source of information. This information is under strict embargo and by taking it into possession, media representatives are committing to the terms of the embargo not only on their own behalf, but also on behalf of the organization they represent.   
----------------------------    

1. Cannabis-based products show limited short-term benefit for chronic pain, with increased risk of adverse effects

Products with higher THC concentration show more improvements in pain severity compared to CBD-only products

Abstract: https://www.acpjournals.org/doi/10.7326/ANNALS-25-03152

Editorial: https://www.acpjournals.org/doi/10.7326/ANNALS-25-04734

Summary for Patients: https://www.acpjournals.org/doi/10.7326/ANNALS-25-03152-PS

URL goes live when the embargo lifts             

A systematic review of trials including more than 2,300 adults with chronic pain found that cannabis-based products with higher tetrahydrocannabinol (THC)-to-cannabidiol (CBD) ratios may provide small short-term improvements in pain and function, especially for those with nerve pain. However, these products are also associated with increased risks of common adverse events. Products with a low THC-to-CBD ratio, including CBD-only formulations, did not appear to be helpful. The review is published in Annals of Internal Medicine.

Researchers from Oregon Health & Science University and colleagues analyzed 25 short-term placebo-controlled randomized trials of cannabis products to update previous evidence about the effectiveness and harms of cannabis-based products for treating chronic pain. The researchers categorized cannabinoids by the ratio of THC to CBD (high, comparable, low); whether the product was synthetic, purified, or extracted from a plant; and administration method (oral, oromucosal, topical) and assessed how well they reduced pain, improved function and whether there were any adverse events. The data showed that oral THC-only products probably slightly reduce pain severity, with the cannabinoids nabilone demonstrating a moderate effect and dronabinol showing no or trivial effect. Nabiximols slightly reduced pain severity and had no meaningful effect on function. Across trials, high and comparable THC products were linked to moderate-to-large increases in adverse events including dizziness, sedation, and nausea. The review highlights the need for more research on long-term outcomes and other cannabis product types.

An accompanying editorial from the UCLA Center for Cannabis and Cannabinoids says the review highlights both the promise and limitations of cannabinoids in treating chronic pain. While THC-based products may offer modest relief, inconsistent study results and safety concerns underscore the need for further research to guide patients, clinicians, and policymakers.

Media contacts: For an embargoed PDF, please contact Gabby Macrina at gmacrina@acponline.org. To contact corresponding author Roger Chou, MD, please email chour@ohsu.edu. 

----------------------------   

2. Once-weekly oral islatravir plus lenacapavir maintains high rates of virologic suppression in adults with HIV

Abstract: https://www.acpjournals.org/doi/10.7326/ANNALS-25-01939

URL goes live when the embargo lifts             

A phase 2 randomized study evaluating the efficacy and safety of once-weekly oral islatravir plus lenacapavir (ISL+LEN) in virologically suppressed adults with HIV found that ISL+LEN maintained high rates of virologic suppression through 48 weeks, with no treatment-related grade 3 or greater adverse events or serious adverse events. These findings suggest that ISL+LEN may offer a promising long-acting oral regimen to address adherence challenges in HIV treatment. The study is published in Annals of Internal Medicine.

Researchers funded by Gilead Sciences evaluated the use of once-weekly ISL+LEN compared with daily oral bictegravir, emtricitabine, and tenofovir alafenamide combination (B/F/TAF) in persons with HIV-1 infection. Outcomes of interest included rates of virologic suppression through week 48 and adverse events. The open-label, active-controlled trial included 104 participants across 44 U.S. sites who had HIV-1 RNA viral load of less than 50 copies/mL while receiving daily B/F/TAF for at least 24 weeks. The participants were randomly assigned to receive either once-weekly ISL (2 mg) plus LEN (300 mg) or continue daily B/F/TAF for 48 weeks. The researchers found that at week 24, one ISL+LEN participant and none in the B/F/TAF group had HIV-1 RNA viral load of 50 copies/mL or more and almost all of the participants in both groups maintained HIV-1 RNA viral load of less than 50 copies/mL. At week 48, viral suppression rates were 94.2% for ISL+LEN and 92.3% for B/F/TAF, with no virologic rebound or emergent resistance detected. Treatment-related adverse events were mild in both groups. There were no discontinuations due to treatment-related adverse events, and changes in CD4+ T-cell and lymphocyte counts were not clinically meaningful. Adherence was high in both groups, with a greater proportion achieving at least 95% adherence in the ISL+LEN group. These results support further evaluation of ISL+LEN in phase 3 trials to assess safety and efficacy in a larger, global study population.

Media contacts: For an embargoed PDF, please contact Gabby Macrina at gmacrina@acponline.org. To contact corresponding author Amy E. Colson, MD please email Brian Plummer at brian.plummer@gilead.com.

----------------------------   

Also new this issue:

Advancing Physical Function Outcomes in Glucagon-Like Peptide-1 Receptor Agonist Trials

Jan H.M. Karregat, PhD; Stuart Phillips, PhD; Maria T.E. Hopman, PhD; Thijs M.H. Eijsvogels, PhD; and Tim Kambič, PhD

Ideas and Opinions

Abstract: https://www.acpjournals.org/doi/10.7326/ANNALS-25-03519

The Enemy

Michael Bretthauer, MD, PhD

Ideas and Opinions

Abstract: https://www.acpjournals.org/doi/10.7326/ANNALS-25-04873