Stephen Ross

Stephen Ross is a psychiatrist specializing in addiction and a leading figure in the revival of clinical research into psychedelic therapy. His path into the field began with a discovery of how much its history had been forgotten; at New York University, he helped turn that recovered history into new studies of psilocybin for cancer-related distress and other conditions. Ross’s work sits at a difficult meeting point: the promise of a powerful, experience-based treatment and the demands of a medical system built to test drugs under controlled conditions.

Rediscovering a buried field

A colleague first alerted Ross to the fact that LSD had been used to treat thousands of alcohol-dependent people in Canada and the United States, and that Bill Wilson, founder of Alcoholics Anonymous, had sought to introduce LSD therapy into the fellowship in the 1950s. Addiction was Ross’s own specialty, yet the history was new to him. In his thirties, he began investigating and found what he understood as an entire body of clinical knowledge missing from his professional education.

The scale of the omission altered his sense of the field. Beginning in the early 1950s, researchers had explored psychedelics as treatments for addiction, depression, obsessive-compulsive disorder, schizophrenia, autism, and anxiety at the end of life. The research involved approximately forty thousand participants and produced more than a thousand clinical papers. The American Psychiatric Association had held meetings centered on LSD, and six international scientific meetings on psychedelics took place between 1950 and 1965. Government-funded studies had engaged prominent psychiatrists in therapeutic approaches to the drugs.

That record had not simply become obscure. After both the culture and the psychiatric establishment turned against psychedelics in the mid-1960s, the research was effectively excluded from the profession’s working memory. By the time Ross entered medical school in the 1990s, he recalled, the subject was no longer discussed. His encounter with this gap gave his later research a historical as well as a clinical purpose: the new studies would have to recover a line of inquiry that earlier researchers had been forced to abandon.

The New York cancer trial

At New York University, Ross directed a clinical trial asking whether a single high dose of psilocybin could ease the anxiety and depression that may follow a life-threatening cancer diagnosis. The trial formed part of a small group of efforts to resume sanctioned psychedelic therapy after research and treatment had largely ended in the 1970s. A sister study took place at Johns Hopkins University under the direction of Roland Griffiths. The renewed work drew on an older research tradition but had to proceed according to contemporary scientific standards.

Ross approached the subject without a personal history of psychedelic use. Before learning about the earlier treatment of alcoholism, he knew little about psychedelics. In the account of the New York trial, he appears as a neatly dressed psychiatrist whose initial response to the results was not immediate certainty but disbelief. He described being unable at first to accept what participants reported after treatment: some encountered their cancer in the form of a dark presence, while others revisited earlier parts of their lives and returned with altered priorities. Patients who had been visibly afraid of death sometimes lost that fear. Ross was struck by the apparent durability of changes after one drug session, an outcome he regarded as unlike anything he had seen in psychiatry.

The experience of Patrick Mettes gave that clinical question a particular human focus. Mettes volunteered for the New York University cancer trial and underwent a turbulent, six-hour psilocybin session guided by palliative-care psychologist Tony Bossis. Ross and Bossis later recounted the session in the treatment room where it had taken place. After about two hours of silence, Mettes began to cry softly and repeated that birth and death involved great effort. Bossis remembered the experience as humbling; Ross’s account of the trial situated such moments within a broader pattern of patients confronting fear and returning with a changed sense of what mattered. The study was not presented as a guarantee of any individual outcome, but Mettes’s session helped show why the researchers were investigating not only a drug’s chemical action but the experience it could occasion.

Findings and renewed clinical interest

In December 2016, results from the New York University and Johns Hopkins cancer studies appeared together in a special issue of the Journal of Psychopharmacology. A front-page New York Times story brought the findings to a wider audience, and nearly a dozen commentaries—including contributions from two former presidents of the American Psychiatric Association—welcomed them. Across the two trials, about 80 percent of cancer patients showed clinically significant reductions in anxiety and depression, with benefits lasting at least six months. The reported intensity of mystical experience closely tracked the degree of symptom relief.

The evidence was promising, but limited in scale: the two studies included eighty subjects altogether, and the findings would need replication in larger trials before the government could consider changing psilocybin’s regulatory status or approving treatment. Even so, the studies drew cautious support from the mental-health community. Medical schools sought to join future trials, and funders came forward. New York University began promoting results from a study it had once treated more hesitantly, and Ross’s treatment room was moved from the dental college into the main hospital. The change in institutional standing did not settle the questions surrounding psychedelic therapy, but it marked a striking shift from the history Ross had uncovered, when the earlier work had gone unmentioned in medical training.

The renewed attention also connected Ross’s research to the older record on addiction. A 2012 meta-analysis of six randomized controlled studies conducted in the 1960s and 1970s, involving more than five hundred patients, found a statistically robust and clinically significant benefit from a single LSD dose for alcohol misuse, lasting as long as six months. In a 2015 pilot study at the University of New Mexico, ten people with alcohol dependence received psilocybin alongside motivational enhancement therapy. The psychotherapy alone had little effect on drinking, but drinking declined significantly after the psilocybin session, and the changes persisted through thirty-six weeks of follow-up. The lead investigator, Michael Bogenschutz, reported that the strength of the experience was strongly associated with its effect on drinking. Encouraged by these results, Bogenschutz began a larger, 180-volunteer phase-two trial at New York University in collaboration with Ross and Jeffrey Guss.

Ross has described alcoholism as involving a profound loss of connection and meaning, in which the substance can come to eclipse relationships and other sources of purpose. That account helps explain why he regards psychedelic treatment as more than the administration of a medication. In the framework articulated by Guss, a co-investigator on the New York trial, psychedelic therapy could bring together approaches that had often been set against one another: biologically based treatment and psychotherapy attentive to meaning. Ross’s research therefore addresses both addiction’s measurable behaviors and the experiences through which patients might understand their lives differently.

From cancer distress to depression

The scope of Ross’s work widened in early 2017, when he and Griffiths brought their cancer-trial results to the Food and Drug Administration seeking permission for a larger phase-three study. The researchers had chosen cancer patients partly because they thought it would be easier to study a controlled substance in people already seriously ill or approaching death. Instead, Food and Drug Administration staff, impressed by the data, urged them to consider a broader question: whether psilocybin might treat depression in the general population. Ross described the exchange as surreal. The agency, according to his account, saw a sufficiently strong indication of possible benefit that the larger problem of depression deserved investigation too.

A similar turn occurred in Europe. In 2016, researchers seeking permission from the European Medicines Agency to study psilocybin for anxiety and depression in people facing life-changing diagnoses were told that existential distress was not an official diagnostic category covered by national health services. Regulators nevertheless saw a possible signal for depression and encouraged a large, multisite study. Their interest reflected not only the New York and Johns Hopkins results but also a feasibility study led by Robin Carhart-Harris in David Nutt’s laboratory at Imperial College London. That study initially involved twelve people with treatment-resistant depression, all of whom had already tried at least two treatments without success. The lack of a control group limited what could be concluded, but participants improved after a week, and two-thirds were depression-free at that point. After the study expanded to twenty people, six remained in remission at six months; others had relapsed to varying degrees. The treatment was well tolerated, with no adverse events reported.

These developments placed Ross’s work inside a debate about what counts as evidence and what kind of intervention psychedelic therapy is. Because participants and guides can often tell whether psilocybin rather than a placebo has been administered, conventional blinding is difficult. The drug’s effects also cannot easily be separated from the session’s setting, the therapist’s presence, and the participant’s expectations. Ross’s research thus helped reopen a clinical field while exposing the methodological challenge at its center: medicine was being asked to evaluate a treatment in which the administered experience, not simply an isolated pharmacological effect, might be crucial. His significance lies in carrying a forgotten history into that unsettled present, where promising findings have widened the questions researchers are permitted to ask without yet removing the need for larger, more rigorous trials.