The drug is Xeljanz, known generically as tofacitinib, and it is manufactured by Pfizer. A landmark clinical trial published in the New England Journal of Medicine found that cancer incidence was 48% higher in patients taking Xeljanz compared to those on older, established alternatives. Specifically, 4.2% of patients on tofacitinib developed cancer versus 2.9% on TNF inhibitors. The FDA responded by slapping its most serious warning label on the drug and restricting its use — yet Xeljanz remains on the market, its sales are growing, and doctors continue to write prescriptions for it. For the millions of Americans managing autoimmune conditions, many of whom are also navigating cognitive decline or caring for someone who is, this is not an abstract regulatory dispute.
It is a direct threat sitting in their medicine cabinet. Xeljanz belongs to a class of medications called JAK inhibitors, approved to treat rheumatoid arthritis, psoriatic arthritis, ulcerative colitis, and ankylosing spondylitis. These are conditions that disproportionately affect older adults — the same population already at elevated risk for both cancer and dementia. The overlap matters. When a 68-year-old woman with rheumatoid arthritis and early cognitive symptoms is prescribed a drug that raises her cancer risk by nearly half compared to available alternatives, the stakes compound in ways that a simple prescribing decision rarely captures. This article breaks down what the clinical data actually shows, why the FDA’s response has been criticized as insufficient, who faces the greatest danger, and what patients and caregivers should be asking their doctors right now.
Table of Contents
- Why Does Xeljanz Raise Cancer Risk, and How Much Danger Are Patients Actually In?
- What Did the FDA Actually Do — and Was It Enough?
- A $3 Billion Market That Keeps Growing Despite the Warnings
- What Patients and Caregivers Should Ask Before Filling the Prescription
- Who Faces the Greatest Risk — and the Cognitive Health Connection
- The Legal Landscape and What It Signals
- What Comes Next for JAK Inhibitors and Patient Safety
- Conclusion
- Frequently Asked Questions
Why Does Xeljanz Raise Cancer Risk, and How Much Danger Are Patients Actually In?
The evidence comes primarily from the ORAL Surveillance trial, one of the largest post-market safety studies ever conducted on an autoimmune drug. The trial enrolled 4,362 rheumatoid arthritis patients aged 50 and older, all of whom had at least one cardiovascular risk factor. Researchers compared tofacitinib against TNF inhibitors — the older class of biologic drugs that had been the standard of care — and tracked outcomes over several years. The results were stark. Among tofacitinib patients, 122 developed cancer, compared to 42 on TNF inhibitors. The hazard ratio was 1.48, meaning patients on Xeljanz had roughly a 48% greater chance of developing a malignancy. Lung cancer and lymphoma appeared at notably higher rates in the tofacitinib group.
To put those numbers in practical terms, the malignancy incidence rate for tofacitinib at the standard 5 mg twice-daily dose was 1.13 per 100 person-years, versus 0.77 per 100 person-years for TNF inhibitors. Researchers calculated a number needed to harm of 55 — meaning for every 55 patients treated with tofacitinib instead of a TNF inhibitor over five years, one additional patient would develop cancer who otherwise would not have. That may sound small in isolation, but across the hundreds of thousands of patients taking the drug globally, it translates to a significant number of preventable cancers. For older adults already juggling multiple health conditions, including neurodegenerative disease, an avoidable cancer diagnosis can be devastating in ways that extend far beyond the tumor itself. It is worth noting that the ORAL Surveillance trial specifically studied patients over 50 with existing cardiovascular risk factors. Whether the same elevated risk applies to younger, healthier patients remains less certain. However, the FDA chose not to limit its warnings to that subgroup — it applied the boxed warning broadly, suggesting the agency believes the signal is strong enough to warrant caution across the board.
What Did the FDA Actually Do — and Was It Enough?
The FDA moved in two phases. In September 2021, the agency issued an initial safety communication based on preliminary data from the ORAL Surveillance trial, flagging increased risks of cancer and cardiovascular events. Three months later, in December 2021, the FDA required boxed warnings — the most serious type of drug label warning — on Xeljanz and extended those same warnings to all JAK inhibitors as a class, including Olumiant (baricitinib) and Rinvoq (upadacitinib). The warnings cover increased risks of serious heart-related events, cancer, blood clots, and death. The FDA also restricted Xeljanz to second-line use, meaning it should only be prescribed to patients who have had an inadequate response to, or cannot tolerate, one or more TNF blockers. On paper, that sounds like a meaningful intervention. In practice, the picture is muddier.
A boxed warning does not remove a drug from the market. It does not prevent a doctor from prescribing it. And the restriction to second-line use is enforced primarily through labeling language, not through hard prescribing barriers in most pharmacy systems. If a rheumatologist decides a patient should try Xeljanz first — whether out of clinical judgment, patient preference for an oral pill over injections, or simple familiarity with the drug — there is little stopping that prescription from going through. For patients with cognitive impairment or their caregivers, who may not think to question a specialist’s recommendation, the boxed warning might never even enter the conversation. However, if a patient has never tried a TNF inhibitor and is being offered Xeljanz as a first option, that should raise an immediate red flag. The FDA’s guidance is clear: TNF inhibitors should be tried first. Patients and caregivers have every right to ask why a drug carrying a boxed warning for cancer and death is being chosen over alternatives that do not carry those same warnings.
A $3 Billion Market That Keeps Growing Despite the Warnings
Perhaps the most unsettling aspect of this story is that Xeljanz sales have not collapsed. The global tofacitinib market was valued at approximately $3.08 billion in 2024 and is projected to reach $3.42 billion in 2025, reflecting a growth rate of about 10.9%. Market forecasts project the drug could generate $7.68 billion by 2032, driven by rising autoimmune disease prevalence and continued prescribing across multiple conditions. Those numbers raise an uncomfortable question: if a drug carries the FDA’s most serious warning for cancer, cardiovascular events, blood clots, and death, why is its market expanding? Part of the answer is convenience. Xeljanz is an oral tablet, while most TNF inhibitors require injections or infusions.
For elderly patients — particularly those with dexterity issues, needle phobia, or cognitive challenges that make injection schedules difficult to manage — a pill is simply easier. Some patients also fail TNF inhibitors or cannot tolerate them, making JAK inhibitors a legitimate medical necessity. But the growth trajectory suggests the drug is being prescribed well beyond that narrow second-line population. One development that could shift the landscape is patent expiration. Pfizer’s key Xeljanz patents are expected to begin expiring from 2025 onward, which may open the door to generic versions. Generics could drive down costs but may also increase access and prescribing volume — potentially putting more patients at risk unless prescribing guidelines are more rigorously enforced.
What Patients and Caregivers Should Ask Before Filling the Prescription
The single most important question to ask is straightforward: have we tried a TNF inhibitor first, and if not, why not? This is not a confrontational question — it is exactly what the FDA’s own guidance recommends. Drugs like adalimumab (Humira), etanercept (Enbrel), and infliximab (Remicade) have decades of safety data and do not carry the same boxed warnings for cancer and cardiovascular events. If your doctor recommends Xeljanz without first attempting a TNF inhibitor, you deserve a clear explanation. The tradeoff is real, though. TNF inhibitors come with their own downsides: they suppress the immune system in different ways, they require injections or infusions, and they can lose effectiveness over time.
For some patients, especially those who have cycled through multiple biologics without relief, a JAK inhibitor may genuinely be the best remaining option. The point is not that Xeljanz should never be used — it is that it should not be used casually, and patients should understand exactly what they are accepting when they take it. For dementia caregivers managing a loved one’s medication regimen, this means reviewing the full list of prescriptions with each specialist and ensuring no one is reaching for Xeljanz simply out of habit. A practical step: request a copy of the medication guide that accompanies Xeljanz prescriptions. It is legally required to include the boxed warning information. If that guide was not provided or discussed at the time of prescribing, that itself is a problem worth raising.
Who Faces the Greatest Risk — and the Cognitive Health Connection
The ORAL Surveillance trial identified clear risk factors. Patients over 65, current or past smokers, and those with a history of heart attack, stroke, or cancer face the highest danger from tofacitinib. This risk profile overlaps almost perfectly with the population most vulnerable to dementia and cognitive decline. Cardiovascular disease and stroke are established risk factors for vascular dementia. Smoking is linked to accelerated cognitive decline. And cancer treatment itself — chemotherapy, radiation, the physiological toll of the disease — is associated with what patients and clinicians sometimes call “chemo brain,” a form of cognitive impairment that can persist for months or years. For a patient already experiencing mild cognitive impairment or early-stage dementia, adding a cancer diagnosis to the picture is not just medically dangerous — it can be functionally catastrophic.
Cancer treatment requires complex decision-making, adherence to multiple new medications, and often significant lifestyle disruption. These demands are difficult enough for cognitively healthy patients. For someone with dementia, they may be impossible to manage without extensive caregiver support. The cascading effect of a preventable cancer in this population is something that risk-benefit analyses rarely capture in full. There is also emerging research into whether chronic inflammation itself — the very thing JAK inhibitors are designed to suppress — plays a role in neurodegeneration. This creates a genuine clinical dilemma: untreated autoimmune inflammation may contribute to cognitive decline, but treating it with a drug that raises cancer risk introduces a different set of dangers. No easy answers exist here, but awareness of the tradeoff is the first step toward a more thoughtful approach.
The Legal Landscape and What It Signals
As of December 2025, individual lawsuits against Pfizer are ongoing, with plaintiffs alleging the company failed to adequately warn about cancer, blood clot, and cardiovascular risks associated with Xeljanz. Over 132,000 adverse event reports have been filed with the FDA through the agency’s FAERS database through 2024 — a staggering volume that reflects the breadth of reported harm. No major settlements have been reached as of early 2026, and the litigation remains in its early stages.
The volume of adverse event reports does not, by itself, prove causation — FAERS data includes unverified reports and can reflect increased awareness rather than increased harm. But 132,000 reports is not background noise. For patients considering their options, the existence of active litigation is worth knowing, not because it should replace medical judgment, but because it signals that the questions surrounding this drug are far from resolved.
What Comes Next for JAK Inhibitors and Patient Safety
The broader class of JAK inhibitors is not going away. These drugs address a real and growing need — autoimmune diseases are becoming more prevalent, and not every patient responds to existing biologics. Pharmaceutical companies are investing heavily in next-generation JAK inhibitors designed to be more selective, potentially reducing the off-target effects that may drive the cancer and cardiovascular risks seen with tofacitinib. Whether that promise holds up in large-scale trials remains to be seen. For now, the practical reality is that patients and caregivers must be their own advocates.
The FDA has issued its warnings. The clinical data is published and peer-reviewed. The drug remains available and profitable. In this gap between regulatory caution and market momentum, informed patients are the last line of defense. If you or someone you care for is taking Xeljanz, the time to have a frank conversation with your prescribing physician is not at the next scheduled appointment — it is now.
Conclusion
Xeljanz is not a rogue drug lurking in the shadows. It is a widely prescribed, FDA-approved medication generating billions in annual revenue. But the ORAL Surveillance trial established that it carries a 48% higher cancer risk compared to TNF inhibitors, and the FDA responded with its most severe warning label. For older adults, smokers, and those with cardiovascular or cancer histories — a population that heavily overlaps with those at risk for dementia — the stakes are disproportionately high. The drug should only be used after TNF inhibitors have been tried and failed, yet market growth data suggests prescribing patterns have not fully aligned with that guidance.
The responsibility here is shared. Physicians need to adhere to second-line prescribing restrictions and have transparent conversations about risk. Patients and caregivers need to ask direct questions and refuse to accept a prescription without understanding why alternatives were ruled out. And for those already taking Xeljanz, a medication review with a knowledgeable provider — not a panicked discontinuation, but a deliberate reassessment — is the right next step. In dementia care, where every additional health crisis compounds an already demanding situation, avoiding a preventable one is not just prudent. It is essential.
Frequently Asked Questions
Is Xeljanz the only drug in its class with a cancer warning?
No. In December 2021, the FDA extended boxed warnings for cancer, cardiovascular events, blood clots, and death to all approved JAK inhibitors, including Olumiant (baricitinib) and Rinvoq (upadacitinib). The concern is considered a class-wide issue, though the strongest direct evidence comes from the ORAL Surveillance trial, which studied tofacitinib specifically.
Should I stop taking Xeljanz immediately if I am on it?
Do not stop any prescribed medication without consulting your doctor. Abruptly discontinuing an autoimmune drug can trigger disease flares that carry their own serious risks. Instead, schedule a conversation with your prescribing physician to discuss whether a TNF inhibitor or another alternative might be appropriate for your situation.
What are TNF inhibitors, and why are they considered safer?
TNF inhibitors — such as adalimumab (Humira), etanercept (Enbrel), and infliximab (Remicade) — are biologic drugs that target tumor necrosis factor, a specific inflammatory protein. They have been used for over two decades and have extensive long-term safety data. In the ORAL Surveillance trial, they served as the comparator group and showed significantly lower rates of cancer, cardiovascular events, and blood clots compared to tofacitinib.
Does Xeljanz affect brain health or dementia risk directly?
There is no direct clinical evidence that tofacitinib causes or accelerates dementia. However, the cardiovascular risks associated with the drug — including blood clots and serious heart-related events — are themselves established risk factors for vascular cognitive impairment and vascular dementia. The indirect connection is meaningful, particularly for older adults already at elevated risk for cognitive decline.
Are there lawsuits I can join if I was harmed by Xeljanz?
Individual lawsuits against Pfizer are ongoing as of early 2026, with plaintiffs alleging inadequate warnings about cancer, blood clot, and cardiovascular risks. No major settlements have been reached yet. If you believe you were harmed, consult a personal injury attorney who specializes in pharmaceutical litigation for guidance specific to your situation.
