Obesity is one of the biggest health issues facing the world today. It increases the chance of getting many dangerous diseases, like heart disease, type 2 diabetes, and even some cancers.
Despite how common it is, there are still very few safe and effective medicines available to treat severe obesity. This leaves many people feeling stuck, especially those who find it hard to lose weight through diet and exercise alone.
But now, researchers at Johns Hopkins Medicine may have found a new way to help. They’ve been studying a drug that was first made to treat Alzheimer’s disease, schizophrenia, and sickle cell disease. It didn’t work for those conditions, but it may be useful for something totally different—helping people lose weight.
The drug blocks a protein in the body called PDE9. This protein, also called an enzyme, helps control some of the body’s chemical reactions. PDE9 affects the heart and metabolism, which includes how the body uses food for energy.
When scientists gave this drug to mice, the animals lost weight, had healthier livers, and better heart health. What’s amazing is that these changes happened without the mice eating less or moving more. This is different from most weight loss strategies, which focus on cutting calories or increasing exercise.
The idea to target PDE9 came from a 2015 study by the same team. They had learned that PDE9 is very active in the heart and can make heart problems worse, especially for people with high blood pressure. So they wondered: Could blocking PDE9 also help with obesity?
The type of drug they tested is called a PDE9 inhibitor. These types of drugs are still being studied and are not available at your local pharmacy. They work a bit like Viagra, which blocks a similar protein called PDE5. Both enzymes affect a chemical called cyclic GMP, which helps control important body functions.
In this new study with mice, researchers looked at whether the PDE9 inhibitor could help with other obesity-related problems too. They studied how it affected blood pressure, blood sugar levels, cholesterol, and belly fat.
The drug they used, called PF-04447943, was first created by Pfizer for Alzheimer’s disease. While it didn’t help with memory loss, it was tested in over 100 people and found to be safe, with no serious side effects.
This is important because so many people are struggling with obesity. In the United States, more than 40% of adults are obese. For women over 60, the number is even higher. If this medicine works the same way in humans as it did in mice, a person weighing 250 pounds could lose about 50 pounds—just by taking a pill, without changing diet or exercise.
The study was led by David Kass and published in the Journal of Clinical Investigation. It offers a fresh way of thinking about weight.
Instead of blaming obesity only on eating too much, it shows that the body’s biology—like the action of enzymes—can also cause people to gain weight. This could mean that future treatments for obesity won’t always require extreme lifestyle changes.
More testing is needed to make sure the drug works safely in humans. But if those studies go well, this discovery could change how we treat obesity and offer real hope to millions of people.
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 about a simple path to weight loss, and results showing a non-invasive treatment for obesity and diabetes.
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