Obesity is one of the biggest health problems in the world today. It can lead to serious illnesses like heart disease, type 2 diabetes, and even some types of cancer.
Even though millions of people are affected, there are still not many safe and effective medicines to treat severe obesity. This makes it even harder for people who are trying to lose weight and keep it off.
But now, scientists at Johns Hopkins Medicine may have found new hope. They have been testing a medicine that was originally designed to treat Alzheimer’s disease, schizophrenia, and sickle cell disease. Although it didn’t work well for those conditions, it may be helpful for treating obesity.
The drug works by blocking a protein in the body called PDE9. This protein helps control some of the chemical processes in our body, including those that affect our heart and how we burn energy. Blocking PDE9 appears to help with obesity and other health problems, at least in mice.
In their recent study, the scientists gave the medicine to mice and saw surprising results. The mice became healthier—they lost fat, had better heart function, and had less fat in their liver. What’s most exciting is that they didn’t have to eat less or exercise more to see these changes.
The idea to study PDE9 came from earlier research back in 2015. At that time, the same scientists discovered that PDE9 made heart problems worse when blood pressure was high. So they asked: could blocking PDE9 also help with health problems linked to obesity?
The medicine used in the study is called a PDE9 inhibitor. This type of drug is still being tested and is not yet available to the public. These drugs are similar to another medicine called Viagra, which works by blocking a related protein named PDE5. Both PDE9 and PDE5 affect a chemical in the body called cyclic GMP, which helps control many important body functions.
In the new study, the researchers wanted to know if blocking PDE9 could do more than just help the heart. They tested to see if it could lower blood pressure, improve blood sugar, lower cholesterol and triglycerides, and reduce belly fat.
The drug they tested was called PF-04447943. It was first created by the company Pfizer to treat Alzheimer’s. It didn’t work for that illness, but when it was tested on more than 100 people, it was found to be safe, with no serious side effects.
This is important because many people today are living with obesity. In the United States, over 40% of adults are obese. Among women over 60, that number goes up to 43%, according to the CDC.
If the drug works in humans the way it did in mice, a person who weighs 250 pounds might lose 50 pounds just by taking a pill—without changing their diet or exercise habits.
The study was led by Dr. David Kass and was published in the Journal of Clinical Investigation. It challenges the old idea that obesity only happens because people eat too much. Instead, it shows that the body’s own biology—like the proteins and enzymes inside us—might play a big role too.
More studies are still needed to know for sure if this medicine works in people and if it is safe for long-term use. But if those studies are successful, this new discovery could help millions of people who struggle with their weight find a safer and easier way to get healthy.
If you care about weight, please read studies about diet that can treat fatty liver disease, obesity, and hop extract could reduce belly fat in overweight people.
For more information about weight, please see recent studies about how to curb your cravings for ready-to-eat foods, and results showing what you can eat to speed your metabolism up.
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