A Cure for Everything? The Rise of Peptides in Modern Medicine

In recent years, peptides have entered the medical mainstream. Biochemists have known these short chains of amino acids for a long time. Many hormones in the human body are, in essence, peptides too. They are present in small amounts and act only briefly. Only recently has pharmacology learned how to work with them skillfully enough to turn natural molecules into fully developed medicines.

One of the best-known peptides that humanity learned to work with more than a century ago is insulin. It has been used in medicine for more than 100 years. One of the biggest recent examples is GLP-1, a peptide hormone that regulates appetite and glucose metabolism.

Originally, drugs based on it were developed exclusively to treat type 2 diabetes. But during clinical trials, something happened that pharmacology might call a plot twist: patients started losing weight rapidly.

That unexpected effect instantly pushed these drugs beyond the realm of endocrinology. First, they moved into obesity clinics, and then into pop culture. Hollywood, social media, and even television quickly turned GLP-1 into one of the most talked-about medical therapies of the decade. Today, it is associated with heavily marketed brand names: first Ozempic from Denmark’s Novo Nordisk, and later Tirzepatide, a dual-action peptide powerhouse from America’s Eli Lilly. We have written about it before.

But the story did not end there. Major studies in recent years have shown that these drugs may affect far more than body weight. They appear to have positive effects on the cardiovascular system, metabolism, and even the brain’s reward centers. A similar plot twist once happened with Viagra: it was originally developed as a treatment for angina and high blood pressure, but in the end, it became famous for a very different side effect – and that is what made the drug legendary.

It is no coincidence that many researchers now speak of GLP-1 not simply as a new drug, but as the beginning of a broader peptide revolution in medicine.

A significant share of GLP-1 research has been conducted, and continues to be conducted, in Massachusetts, at research and medical centers in Boston and Cambridge. Biotech companies and startups in Cambridge are now helping develop new peptide drugs and the technologies used to manufacture them. Thanks in part to comments by the U.S. Health Secretary Robert F. Kennedy Jr., America is also discussing whether peptides could eventually be used more broadly, from new therapeutic indications to possible advances in longevity.

• But any conversation about peptides is not only a conversation about pharmacology’s scientific advances. It is also a story about enormous investment and big business. Revenue from the GLP-1 drug class is expected to exceed $100 billion by 2030.

This article continues the subject we explored in our 2025 piece, A Breakthrough in Weight Loss

Since then, the topic has become even more relevant. Today, we offer readers a ten-minute deep dive into peptides. When the conversation is about health, quality of life, and longevity, it is time well spent. And if you prefer an audio format, listen to the podcast.

Peptides: a new biohacker fad or the next pharma platform?

Peptides are short chains of amino acids that serve as signaling molecules in the body. Through them, cells and organs exchange chemical messages: appetite, metabolism, and hormonal function are all regulated this way. This group includes many hormones, including insulin and GLP-1.

For a long time, peptides were considered inconvenient for pharmacology. Natural hormones break down quickly in the body, which is why most 20th-century medicines were built around simpler chemical molecules. In recent decades, that has changed. Modern bioengineering allows scientists to modify natural peptides, making them more stable and longer-lasting. If natural hormones survive in the bloodstream for only a matter of minutes, pharmaceutical versions can work for hours or even weeks. That is exactly what made today’s GLP-1 drugs possible.

At the same time, another phenomenon emerged: peptide biohacking. The internet now sells dozens of so-called research peptides. Formally, they are intended for laboratory use, but in practice, many people use them for weight loss, muscle growth, or even rejuvenation.

Regulators are increasingly warning about the risks of these experiments. The FDA has already sent warning letters to companies selling unapproved peptides under the guise of research reagents. We will return to that gray market at the end of the article. That is why, against the backdrop of this industry, drugs that have gone through full clinical trials and become part of mainstream medicine stand out so clearly. The best-known example today is GLP-1.

GLP-1: how a diabetes drug became a weight-loss treatment

GLP-1 (glucagon-like peptide-1) is a hormone produced by the gut after eating. It reduces appetite, stimulates insulin release, and slows gastric emptying. It is one of the signals the body sends to the brain, indicating that it has already received enough energy.

Drugmakers began using synthetic versions of the hormone to treat type 2 diabetes. These drugs help stabilize glucose levels and improve metabolism. But during clinical trials, doctors noticed an unexpected effect: patients began losing significant weight.

The weight loss was so pronounced that GLP-1-based drugs quickly moved beyond diabetology. They began to be used in obesity treatment and soon entered a much broader medical conversation.

As a result, GLP-1 became a rare example of a drug that transformed two major areas of medicine at once: diabetes therapy and obesity treatment.

From weight loss to the heart and brain: does GLP-1 look like a cure for everything?

As more data accumulated, it became clear that GLP-1’s effects are not limited to weight loss. More and more often, these drugs are being viewed as a broader metabolic therapy. Studies in recent years suggest that drugs in this class may affect several systems in the body at once. Researchers are now actively studying their effects on:

• heart failure;
• fatty liver disease;
• kidney disease;
• sleep apnea;
• various forms of addiction.

The reason for this wide range of action is that GLP-1 receptors are found not only in the pancreas, but also in the heart, blood vessels, kidneys, and brain.

Its effect on the brain’s reward centers has proved especially interesting. In some studies, patients report reduced cravings not only for food, but also for alcohol and other forms of craving. That is why more and more researchers are discussing GLP-1 not simply as a weight-loss drug but as a potential new therapeutic platform.

Nota bene: Boston and Cambridge as part of the peptide ecosystem

Massachusetts’ scientific ecosystem plays an important role in advancing this field. Research on peptides, including GLP-1, is actively underway at Harvard Medical School, Massachusetts General Hospital, Mass General Brigham, and MIT.
At the same time, biotech companies and laboratories continue to emerge, working on technologies to synthesize complex peptides and develop new hormone-based drugs.
MIT, in particular, is developing methods to speed up the production of long peptide molecules that may be used in future generations of medicines.

The next step: from injection to pill

Today’s generation of GLP-1 drugs, including tirzepatide, is delivered by injection. The reason is simple: peptides do not survive well in the stomach’s acidic environment and break down quickly, making it extremely difficult to deliver them in a standard pill. To work around that problem, pharmacologists are developing delivery systems with protective coatings and chemical modifications to the molecules. These allow the drug to pass through the stomach and be released later in the intestine. At the same time, doses have to be increased to compensate for the amount of the substance lost as it passes through the digestive system.

The race for the magic pill is already in full swing. Eli Lilly has developed an oral drug, orforglipron, that acts on the same GLP-1 receptor. The company has already submitted documents to the FDA, and a regulatory decision is expected in April 2026.

Once tablet versions reach the market, GLP-1 therapy could become even more widespread. The shift from injection to pill is a familiar path for many medicines. Insulin, however, the first peptide drug in medical history, is still delivered by injection more than a century later.

The dark side of the trend: the peptide gray market

The popularity of GLP-1 has also created a dangerous side trend. The internet is full of experimental peptides that people buy for self-injection.

Formally, such substances are labeled as research peptides. In practice, however, they are often used as illegal drugs. Among the most common substances sold on this market are:

Some peptides, such as Epitalon, popular in the biohacking community, originate in Soviet or Chinese gerontological research. Their effectiveness raises serious doubts: the evidence base is limited, and there have been almost no major international clinical trials.Skepticism is reinforced by the broader crisis of trust in such sources. In recent years, Putin’s Russia has been at the center of major international doping scandals involving the use of banned substances during the highly publicized Sochi Olympics. The consequences were profound: the country’s Olympic team was effectively drained of its competitive strength, and Russian athletes faced sweeping sanctions, including bans from major international competitions.

And beyond that, the fact that Russian intelligence services have used rare synthetic poisons to kill political opponents has further undermined trust in Russian medical developments.

Nota bene: one more surprise from peptides

Research on retatrutide, a new peptide drug being developed by Eli Lilly, suggests that drugs in this class may prove not just effective, but perhaps too effective.

According to The New York Times, preliminary trials showed that people with obesity and knee osteoarthritis lost 28.7% of their body weight after taking the maximum dose of the drug for nearly 70 weeks. By comparison, patients using the currently available weight-loss drugs lost about 20% over the same period.

As a result, up to 18% of participants dropped out of the trials because they felt they were losing too much weight. The study is not yet complete, but the situation is already raising concerns about weight-loss drugs.

Conclusion

Peptides are gradually evolving from a laboratory curiosity into a new pharmacological platform. The history of insulin, the century-long experience of using it, and the story of GLP-1 show how a single hormone can ease and extend life, reshape several areas of medicine – from diabetes treatment to obesity therapy and cardiovascular care – and possibly even influence longevity in good health, which is, ultimately, the goal.

Thank you for taking the time to read this article or listen to the podcast.

But caution is essential in this field, as it is with anything new. The central question of the coming years is which of these new peptides will become real medicines, and which will remain trapped in the shadows of the gray market.

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