Robert L. McNeil, Jr.

Robert McNeil, Jr., at the Chemical Heritage Foundation. Photograph by Douglas Lockard. CHF Collections.

Robert McNeil, Jr., at the Chemical Heritage Foundation. Photograph by Douglas Lockard. CHF Collections.

Even before aspirin was created (see Felix Hoffmann), the active ingredient in one of today’s most popular pain relievers and fever reducers, Tylenol, had been discovered by scientists in Europe. But because toxicology and pharmacology were still in their early stages in the late 19th century, this substance—N-acetyl p-aminophenol—was left on the shelf for over 50 years. In the mid-20th century researchers in the United States began to take an interest in the possibilities of this substance, conducting studies that demonstrated its efficacy and safety as an analgesic and antipyretic. Seeing opportunity, in 1954 McNeil Laboratories of Philadelphia, at the urging of Robert L. McNeil, Jr. (1915–2010), undertook the final laboratory and clinical testing needed to gain approval for the drug from the U.S. Food and Drug Administration (FDA) and then marketed it.

McNeil, Jr., then vice president of production and development, became interested N-acetyl p-aminophenol during an informal conversation with Raymond Conklin, vice president of the Institute for the Study of Analgesic and Sedative Drugs, at an American Pharmaceutical Manufacturers Association meeting. The institute, formed in 1939, had been conducting basic research on the substance. Their recent findings, according to Conklin, showed that N-acetyl p-aminophenol appeared to be free from side effects in normal dosage. Earlier, good reports coming out of Yale and New York universities had led several American pharmaceutical companies to begin manufacturing products containing N-acetyl p-aminophenol, but their sales efforts had thus far been halfhearted, largely because they feared that the new products would adversely affect sales of their aspirin-based products. As McNeil spoke with Conklin, his interest was piqued.

The interior of McNeil’s Drug & Prescription Store at Front and York Streets in Philadelphia, 1900. Courtesy McNeil Consumer Healthcare.

The interior of McNeil’s Drug & Prescription Store at Front and York Streets in Philadelphia, 1900. Courtesy McNeil Consumer Healthcare.

McNeil represented the third generation of his family at McNeil Laboratories. The company had evolved from a neighborhood pharmacy established in Philadelphia in 1879 by his grandfather. Until the 1930s it had specialized in selling hundreds of drugs to physicians who dispensed them without prescription to their patients. After earning a B.S. in physiological chemistry and bacteriology at Yale University in 1936, McNeil entered the family business in 1937, while completing a second bachelor’s degree at the Philadelphia College of Pharmacy (now University of the Sciences in Philadelphia). He simultaneously pursued graduate studies at Temple University. McNeil was soon made responsible for reevaluating the company’s product line, reorganizing its departments, and creating a research-and-development division to develop prescription products that would comply with the “safe for use” requirements of the federal Food, Drug and Cosmetic Act of 1938.

Upon his return from the pharmaceutical manufacturers meeting and his conversation with Ray Conklin, McNeil had the head of the firm’s medical sciences division and the head of its clinical investigation division confirm the significance of Conklin’s verbal report on N-acetyl p-aminophenol. He then convened a meeting of the firm’s New Products Committee, which included these scientists as well as his brother Henry, then vice president of marketing, and the directors of sales, advertising and promotion, and market planning.

Presented with a proposal to put N-acetyl p-aminophenol on the market, the marketing and sales executives on the New Products Committee raised the obvious question: why try to sell a drug to compete with aspirin that would cost more than aspirin? McNeil convinced the doubters by pointing out that the drug had antipyretic and analgesic properties similar to those of aspirin but did not cause the stomach irritation that aspirin often did, especially when taken too frequently. Furthermore, McNeil planned to aim at a different niche: developing a drug that the marketing division could promote to physicians for them to prescribe—not an over-the-counter product that would compete directly with aspirin.

Unlike many other pharmaceutical companies, McNeil Labs did not have its own aspirin product and did not have to fear such competition. As the McNeil plan evolved, the pediatric field was targeted, with the objective of developing a liquid-dosage form for children. First McNeil’s pharmacology department confirmed the pharmacologic and toxicologic conclusions of the research groups at the Institute for the Study of Analgesic and Sedative Drugs and of other researchers. Clinical trials of a pediatric elixir were conducted in cooperation with pediatricians, and gastroenterologists studied the local erosion effect of aspirin’s hydrolyzing in the stomach to acetic acid and salicylic acid—and demonstrated it in vivo to the marketing executives! The pharmaceutical development department prepared a special solvent system for the elixir that kept the active ingredient in solution but was low in alcohol and palatable to young patients. The director of market planning coined the name Tylenol from the drug’s chemical name, and McNeil suggested acetaminophen as the generic term. The marketing group then proceeded with plans to introduce Elixir Tylenol, using the slogan “for little hotheads” in the caption for the outer carton, which was shaped like a fire engine. Six months after the decision by the New Products Committee to proceed with N-acetyl p-aminophenol, the FDA granted its approval, and Elixir Tylenol was introduced in June 1955.

Not long afterward, McNeil Laboratories was purchased by Johnson & Johnson. As part of Johnson & Johnson, McNeil Labs developed and gained FDA approval for a line of Tylenol with codeine, which eventually became the most frequently prescribed of any pharmaceutical brand, followed by other dosage forms and combinations of Tylenol for sale to hospitals and over the counter in drugstores.

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