TL;DR
Knee arthritis turns stairs, walks and a night's sleep into a negotiation with pain, and extra body weight makes every step heavier on the joint. Now the full results of two large trials, published in the New England Journal of Medicine, show one weekly drug easing both problems at once. Eli Lilly's retatrutide, which acts on three appetite-and-metabolism hormone receptors, helped adults with obesity and painful knee arthritis lose about 17 to 25 percent of their body weight, and 63 to 70 percent of treated patients cut their knee pain by at least half, against 38 percent on a placebo. That is the first time a drug has lowered both the load on the knee and the pain in the same trial at this scale. Our odds that it gets a U.S. approval for people with obesity and knee arthritis by 2028: 50%. For the full odds board and the timeline of breakthroughs that could take people from less pain to rebuilt joints, subscribe.
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