For decades, the pharma industry had little appetite for weight-loss drugs. This was not surprising, given the numerous high-profile failures and safety scandals that had filled the obesity space.
In the 1940s, pharma companies began promoting amphetamines, such as Benzedrine sulfate tablets, for their ability to suppress appetite. Manufacturers combined amphetamines with thyroid extracts, diuretics and laxatives to create obesity drugs. The highly addictive “rainbow diet pills” caused serious side effects, ranging from cardiovascular risks and organ failure to death, before being banned in 1968.
On Sep. 23, 1996, the cover of Time magazine featured a fit woman in a bathing suit alongside the headline, “The Hot New Diet Pill.” Redux capsules, marketed by Wyeth-Ayerst Laboratories, had been approved by the FDA as an anti-obesity treatment in April 1996, marking the first new diet drug in the U.S. in 23 years. Just three months after Redux’s introduction, doctors were writing 85,000 prescriptions a week.
Redux, however, was just a refined version of fenfluramine, an appetite suppressant that boosted serotonin. Since the early 1990s, doctors had been prescribing fenfluramine along with the stimulant, phentermine, off label — a “magic pill” cocktail known as the Fen-Phen diet. Redux and fenfluramine were both linked to heart valve damage and primary pulmonary hypertension before being withdrawn from the market in 1997. In the thousands of lawsuits that followed, plaintiffs’ attorneys forced Wyeth to disclose its own trial data, which included 29 deaths that had never been reported to the FDA.
After decades of documented industry failures in the obesity space, the approvals of Novo and Eli Lilly’s injectable GLP-1 receptor agonists represented a turning point in obesity medicine, offering pharmacological treatments with demonstrated efficacy and established safety profiles.
The approvals and subsequent patient demand, however, also caused chaos. The race to secure sterile fill-finish capacity, equipment and workers upended the industry. Meanwhile, shortages gave rise to an illegal compounding market, as well as dangerous counterfeits.
There are now two approved weight-loss tablets on the market — Novo’s oral Wegovy and Eli Lilly’s Foundayo. And oral solid dose, the industry’s oldest manufacturing workhorse, must prepare to confront a GLP-1-sized appetite.
On paper, this shift away from sterile injectables should ease the pressure. Without the need for aseptic processing, isolators or extensive clean room infrastructure, tablets are faster to develop and cheaper to scale than sterile injectables.
But the picture is more complicated. Formulation matters. An oral peptide, such as the Wegovy pill, will face different manufacturing challenges than a small molecule, such as Foundayo. As new entrants come to market, they will need to offer not only safety and efficacy, but also a clear and sustainable manufacturing plan.
For manufacturers, that means planning ahead and developing a strategy tailored to each molecule.
The bottleneck, in other words, hasn’t disappeared. Like weight gain, it doesn’t settle in just one place; it can show up across different parts of the process.