Every weekly injection of Ozempic or Wegovy rests on a question that had to be answered in a laboratory first: which version of the gut hormone GLP-1 actually tells the pancreas to release insulin?
Svetlana Mojsov, a peptide chemist now at Rockefeller University, helped answer that question in the 1980s. Her work established the biological importance of GLP-1(7-37), a shortened form of the hormone that became foundational to modern diabetes and obesity medicines.
For years afterward, the story of GLP-1 was often told without her. Patents originally named a former collaborator as the sole inventor, and several prestigious scientific awards recognized other researchers while leaving her out.
The recognition eventually came. After a long dispute over inventorship and scientific credit, Mojsov received major international prizes, including the 2024 Lasker-DeBakey Clinical Medical Research Award, the 2025 Breakthrough Prize in Life Sciences and the 2026 King Faisal Prize in Medicine.
Her story is not that one scientist invented Ozempic. It is about how a critical piece of a medical breakthrough was established, how its author struggled to receive recognition, and how the scientific record eventually caught up.
Svetlana Mojsov, a Peptide Chemist From Skopje
Mojsov was born in Skopje, then part of Yugoslavia and now the capital of North Macedonia. She studied physical chemistry at the University of Belgrade, graduating in 1971, before moving to New York in 1972 for graduate research at Rockefeller University.
There she trained in the laboratory of Bruce Merrifield, the chemist who pioneered solid-phase peptide synthesis, a method for assembling peptides one amino acid at a time using a solid support.
Merrifield’s method transformed peptide chemistry by making it possible to produce defined molecules with greater efficiency and control. He received the Nobel Prize in Chemistry in 1984 for developing the technique.
Mojsov earned her PhD in biochemistry in 1978 and remained at Rockefeller as a postdoctoral researcher and later a research associate.
Her expertise was unusually valuable for endocrinology. Researchers could identify a possible hormone from a gene sequence, but proving its biological function often required someone who could manufacture the exact peptide and distinguish it from closely related molecular forms.
In 1983, Mojsov moved to Massachusetts General Hospital, where she joined the Endocrine Unit as an Assistant in Biochemistry and became the founding director of the Howard Hughes Medical Institute peptide synthesis facility. She also served as an Instructor in Medicine at Harvard Medical School.
At MGH she worked in an environment where researchers, including endocrinologist Joel Habener, were investigating the glucagon gene and the peptides encoded within its precursor protein.
The problem appeared technical. The implications would prove enormous.
Which GLP-1 Is the Biologically Active Hormone?
The glucagon gene encodes a larger precursor protein called proglucagon. Enzymes process that precursor into several smaller peptides, including glucagon and the glucagon-like peptides GLP-1 and GLP-2.
By the early 1980s, molecular biologists had identified sequences corresponding to these peptides. What remained uncertain was precisely how the precursor was processed and which of the resulting molecules carried biological activity.
GLP-1 was especially intriguing because researchers had long suspected that the intestine produced hormones capable of stimulating insulin secretion after food intake.
Those hormones are known as incretins. They help explain why glucose taken orally can stimulate a greater insulin response than the same glucose delivered directly into the bloodstream.
According to Rockefeller University’s historical account, Mojsov recognized a potential processing site in the proposed GLP-1 sequence. She suspected that a shortened peptide beginning at amino acid seven, rather than the longer 37-amino-acid sequence, might be the relevant biological molecule.
She synthesized different GLP-1 forms and developed analytical tools to identify the peptides in biological tissues.
A 1986 paper in the Journal of Biological Chemistry, with Mojsov as first author, helped establish that proglucagon undergoes different processing in the pancreas and intestine, producing distinct peptide products.
The decisive functional evidence followed in February 1987.
In the Journal of Clinical Investigation, Mojsov, Gordon Weir and Habener reported experiments comparing synthetic GLP-1 peptides in an isolated, perfused rat pancreas.
The difference between the two forms was dramatic.
GLP-1(1-37), the longer 37-amino-acid peptide, did not stimulate insulin secretion under the experimental conditions, even at concentrations as high as 5 × 10-7 molar.
GLP-1(7-37), the shorter 31-amino-acid peptide, produced three- to tenfold increases in insulin secretion over baseline at concentrations as low as 5 × 10-11 molar in the presence of glucose.
The experiment provided powerful evidence that removing the first six amino acids was crucial to the hormone’s insulin-stimulating activity.
Other biologically active forms, including GLP-1(7-36) amide, would also become important in understanding incretin physiology. The discovery should therefore be understood as identifying the importance of the processed, active GLP-1 hormone, not establishing that only one molecular form can work.
The longer peptide did not stimulate insulin in the experiment. The shortened form triggered a strong response at remarkably low concentrations.
The next question was whether that result mattered outside an isolated rat pancreas.
In February 1992, a study published in Diabetes Care by David Nathan, Eric Schreiber, Howard Fogel, Mojsov and Habener examined GLP-1(7-37) in people with and without diabetes.
The researchers found that the peptide stimulated insulin secretion and could improve glucose regulation, providing early human evidence of its therapeutic potential.
That did not mean an immediately practical drug existed. Naturally occurring GLP-1 has a short biological lifetime, and converting the hormone into a convenient medicine would require years of further pharmacological engineering.
But the central biological question had been answered: an active form of GLP-1 could stimulate insulin release in a glucose-dependent setting, making the pathway a credible target for diabetes treatment.
The GLP-1 Patents That Originally Left Her Name Off
Mojsov returned to Rockefeller University in 1990, becoming an assistant professor and continuing her research on peptide hormones.
Meanwhile, Massachusetts General Hospital was pursuing patent protection for GLP-1-related discoveries.
According to a 2023 investigation by journalists Elaine Chen and Megan Molteni at STAT, Mojsov had previously discussed patent protection with MGH’s intellectual property office and shared laboratory notebooks documenting her work.
She told STAT that she did not receive follow-up information about those discussions.
Two foundational GLP-1 patents were granted in 1992 listing Joel Habener as the sole inventor.
The patent issue surfaced in a memorable encounter described in STAT’s investigation.
At the first International Symposium on GLP-1, held in Copenhagen in May 1993, Mojsov encountered Habener and asked whether he had heard anything about a patent.
According to Mojsov’s account to STAT, Habener turned away without answering. That is her recollection of the interaction, not an independently established account of his intentions.
Mojsov learned in 1996 that patent rights had been secured without naming her as an inventor, according to Rockefeller University’s account.
She subsequently pursued correction of the inventorship records, a process that required years of legal effort.
The corrections occurred over time rather than through a single action in 2006.
United States patent records show certificates correcting inventorship on GLP-1 patents in 2004. Further corrections and patent actions followed through 2006.
Rockefeller’s historical account states that four MGH patents were ultimately corrected to include Mojsov as a co-inventor.
Those records matter because patent inventorship and scientific authorship are different forms of recognition. Being listed as an author on a scientific paper does not automatically establish inventorship, but inventorship must accurately reflect qualifying contributions to the patented claims.
Mojsov’s dispute was therefore about more than an academic acknowledgment. It concerned whether legal records covering applications of the discovery properly recognized her contribution.
The patents were eventually corrected. But recognition in the wider scientific community would take longer.
Left Out of Major Awards, Then Recognized
As GLP-1-based medicines developed into successful therapies, researchers associated with the pathway received increasingly prestigious scientific recognition.
In earlier award cycles, major honors went to combinations of scientists including Habener, Daniel Drucker and Jens Juul Holst. Mojsov was not among the recipients of several prizes recognizing GLP-1 research.
The omission drew renewed attention after the 2023 STAT investigation and additional reporting about the history of GLP-1 discovery.
Mojsov’s stated objective was to have her scientific contributions accurately acknowledged. Speaking to Rockefeller University, she explained: “I just wanted my papers to be known.”
That is an important distinction. Her original research papers had not disappeared. The 1986 and 1987 publications remained part of the literature. The problem was how the discovery was being summarized, attributed and celebrated.
The recognition changed substantially in 2024.
Mojsov received Rockefeller University’s Pearl Meister Greengard Prize, shared the Tang Prize in Biopharmaceutical Science, and was named to TIME’s list of the world’s 100 most influential people.
In September 2024, the Lasker Foundation announced that she would share the Lasker-DeBakey Clinical Medical Research Award with Habener and Novo Nordisk scientist Lotte Bjerre Knudsen.
The foundation described Mojsov and Habener’s contributions to identifying physiologically active GLP-1, while recognizing Knudsen’s leadership in developing long-acting medicines based on the hormone.
The award brought together two stages of the GLP-1 story: discovering the active hormone and transforming its biology into medicines that patients could use.
Recognition continued in 2025.
Mojsov received the Breakthrough Prize in Life Sciences, was elected to the United States National Academy of Sciences and received the Distinguished Medical Science Award from the National Library of Medicine.
She also received the Warren Triennial Prize from Massachusetts General Hospital, the institution whose patent records she had spent years seeking to correct.
In January 2026, she was announced as the King Faisal Prize in Medicine laureate for discoveries that helped transform obesity treatment.
On May 20, 2026, Rockefeller University announced her promotion to the Lulu Chow Wang and Robin Chemers Neustein Research Professor position.
It was another institutional acknowledgment of research that had begun more than four decades earlier.
The scientific papers established her contribution in the 1980s. The patent corrections came years later. The biggest awards followed decades after the experiments.
What the History of GLP-1 Discovery Does Not Settle
Recognizing Mojsov’s contribution does not mean the discovery of GLP-1 belongs exclusively to one researcher.
Multiple laboratories were investigating proglucagon, incretin physiology and related peptides during the 1980s and early 1990s.
Habener’s laboratory contributed important molecular biology research. Daniel Drucker helped investigate proglucagon processing and GLP-1 biology. Jens Juul Holst and other researchers independently advanced understanding of the hormone’s physiological actions.
Gordon Weir was a co-author of the 1987 experiment demonstrating GLP-1(7-37)’s insulin-stimulating activity in the perfused rat pancreas.
Later, scientists working on drug development had to solve an additional problem: natural GLP-1 is broken down rapidly and cannot simply be administered like a conventional long-acting medicine.
At Novo Nordisk, Knudsen and her colleagues developed modified GLP-1 analogs with properties that made them suitable for therapeutic use.
That work eventually contributed to liraglutide and semaglutide, medicines whose pharmacological profiles differ substantially from naturally occurring GLP-1.
Grey Pepper has examined Knudsen’s contribution in its profile of the scientist behind semaglutide’s development.
Those additional contributions do not diminish Mojsov’s role. They illustrate why the historical development of a drug class rarely has a single discoverer.
There are also limits to what the public record establishes about the recognition dispute.
The scientific papers, patent corrections and award records can be independently examined. More personal details of the dispute rely partly on interviews and Mojsov’s recollections.
Habener has publicly acknowledged the significance of her contribution. In comments reported by the Boston Globe in 2024, he described her as instrumental in their collaborative work.
The careful conclusion is not that every other scientist received undeserved recognition. It is that Mojsov made a documented, substantial contribution to identifying biologically active GLP-1, and the public recognition of that contribution was incomplete for many years.
Why Svetlana Mojsov’s Story Matters Now
GLP-1 drugs are now among the most commercially important medicines in the world. Their development has changed treatment options for type 2 diabetes and obesity and expanded research into cardiovascular, kidney and other metabolic diseases.
Yet the origins of that drug class were not a commercial product, a clinical marketing campaign or an obesity trial.
They included fundamental experiments in peptide chemistry and endocrinology, when scientists were still establishing which fragments of a hormone precursor were biologically active.
Mojsov’s work demonstrated why molecular precision matters. Removing six amino acids from a 37-amino-acid peptide changed its activity dramatically in the experiments that helped establish GLP-1 physiology.
Later researchers modified the molecule further to overcome rapid degradation and extend its duration of action.
Readers can follow that next stage in Grey Pepper’s examination of how semaglutide was engineered to remain active for approximately a week.
The scientific connection is direct, even though the modern medications are not chemically identical to the hormone Mojsov synthesized.
Her story also shows how scientific recognition can become detached from the original documentary record.
A paper may accurately list its authors while later accounts emphasize only a few names. Patent records can require correction. Prize citations can reinforce established narratives, particularly when the history involves several laboratories and decades of research.
The renewed recognition of Mojsov’s work does not rewrite the original experiments. It directs attention back to them.
In 1987, her name was already on the paper demonstrating that GLP-1(7-37) strongly stimulated insulin secretion. By 1992, she was a co-author on research extending its physiological effects to humans.
The evidence of her contribution was there long before the most prestigious awards arrived.
For a scientist who said she wanted her papers to be known, that may be the most significant outcome of the renewed attention.
The recognition came late. The experimental record had been there for decades.
Sources and Further Reading
- Mojsov S, Weir GC, Habener JF. Insulinotropin: glucagon-like peptide I (7-37) co-encoded in the glucagon gene is a potent stimulator of insulin release in the perfused rat pancreas. Journal of Clinical Investigation, February 1987.
- Mojsov S, Heinrich G, Wilson IB, Ravazzola M, Orci L, Habener JF. Preproglucagon gene expression in pancreas and intestine diversifies at the level of post-translational processing. Journal of Biological Chemistry, September 1986.
- Nathan DM, Schreiber E, Fogel H, Mojsov S, Habener JF. Insulinotropic action of glucagonlike peptide-I-(7-37) in diabetic and nondiabetic subjects. Diabetes Care, February 1992.
- Rockefeller University. Svetlana Mojsov: historical account of her GLP-1 research and recognition dispute.
- Chen E, Molteni M. The Ozempic revolution is rooted in the work of Svetlana Mojsov, yet she’s been edged out of the story. STAT, September 27, 2023.
- Molteni M, Chen E. Long-overlooked scientist shares Lasker Award with other GLP-1 researchers. STAT, September 19, 2024.
- Lasker Foundation. GLP-1-based therapy for obesity: 2024 Lasker-DeBakey Clinical Medical Research Award.
- Rockefeller University. Svetlana Mojsov promoted to Research Professor, May 20, 2026.
- King Faisal Foundation. Announcement of the 2026 King Faisal Prize in Medicine awarded to Svetlana Mojsov, January 2026.
- National Academy of Sciences. Svetlana Mojsov: member biography and scientific career.
