A new study from Johns Hopkins Medicine has found that a drug first designed for treating brain diseases and other illnesses might also help people lose weight and stay healthier—without needing to change their diet or exercise habits.
The drug, which was originally made to treat Alzheimer’s disease, schizophrenia, and sickle cell disease, showed surprising results in fighting obesity. This is especially important because severe obesity is a growing global problem.
It increases the risk of many serious health issues like heart disease, diabetes, and liver problems. Right now, there is no simple pill that works well to treat this condition.
In this new research, scientists studied a protein in the body called PDE9. This protein helps control a molecule called cyclic GMP, which is involved in many processes inside our cells. PDE9 is related to another protein called PDE5, which is the target of well-known drugs like Viagra.
Scientists are still studying PDE9 inhibitors, and there isn’t a drug using them on the market yet. But drug companies are testing them for several illnesses, such as Alzheimer’s and heart failure.
Back in 2015, the same research team discovered that PDE9 plays a role in damaging the heart, especially in people with high blood pressure.
Building on that, they decided to find out if blocking PDE9 could also help with problems like obesity, high blood pressure, high cholesterol, and high blood sugar. These are all common in people with metabolic syndrome.
To test their idea, the team used mice and gave them a PDE9-blocking drug called PF-04447943. This drug was developed by the company Pfizer and was once studied for Alzheimer’s disease. Even though it was not used for that purpose, tests had shown it was safe in over 100 people, and there were no major side effects.
When the researchers gave this drug to mice, they saw impressive results. The mice lost weight, had less fat in their liver, and their hearts worked better. All of this happened without any change in their food or activity. The mice kept eating the same food and moving the same amount, but still got healthier.
If these effects also happen in humans, the impact could be huge. For example, someone who weighs 250 pounds might lose about 50 pounds just by taking the drug. It could also help improve their heart health and reduce other health risks linked to obesity.
This is very promising because in the U.S. alone, more than 40% of adults are obese. For women over age 60, the number is even higher—43%. Many people try to lose weight by changing their diet or exercising more, but it doesn’t always work. A safe drug that can help would be a big step forward.
It’s still early, and more studies are needed to see how the drug works in people. But another PDE9-blocking drug is already being tested in human clinical trials for heart problems, which adds hope that this class of drugs could be helpful for weight loss too.
The study was led by Dr. David Kass and published in the Journal of Clinical Investigation. It gives new hope to people dealing with obesity and related health problems and could improve the lives of millions in the future.
If you care about weight loss, please read studies that hop extract could reduce belly fat in overweight people, and early time-restricted eating could help lose weight.
For more health information, please see recent studies that Mediterranean diet can reduce belly fat much better, and Keto diet could help control body weight and blood sugar in diabetes.
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