When the UK National Health Service (NHS) introduced biosimilar versions of adalimumab (Humira) at roughly 80% below the original list price, the goal was straightforward: deliver cost-effective treatment for inflammatory conditions like psoriasis to more patients. Yet for many people living with moderate-to-severe plaque psoriasis, accessing these cheaper biologics has become a bureaucratic obstacle course. Prior authorization requirements and step therapy protocols—mandating that patients try and fail on older, cheaper drugs first—have created delays that dermatologists argue are both clinically harmful and economically questionable.

A Cost-Saving Policy That Delays Care

Under current NHS commissioning policies, clinical commissioning groups (CCGs) and integrated care boards (ICBs) often require patients to undergo prior authorization before receiving a biosimilar adalimumab prescription. Even when a dermatologist recommends a biologic as first-line therapy for severe psoriasis—consistent with NICE guidelines—the patient must first fail on conventional systemic treatments such as methotrexate or ciclosporin. This step therapy approach, designed to curb spending, means weeks or months of ineffective treatment while disease activity progresses.

Dr. Sarah Jenkins, a consultant dermatologist at a large teaching hospital in Manchester, describes the process as “frustratingly slow.” She notes that for patients with severe psoriasis covering more than 10% of body surface area, delays of six to eight weeks for approval are common. “By the time the prior authorization comes through, the patient’s quality of life has often deteriorated significantly,” she says. “We see increased pain, itching, and in some cases, the development of psoriatic arthritis, which could have been prevented with earlier biologic intervention.” The administrative burden falls heavily on GP practices, which lack specialist input to navigate the approval forms. A 2024 survey by the British Association of Dermatologists found that roughly 70% of dermatologists reported their patients’ psoriasis worsening during the prior authorization waiting period. Some clinics report that 20–30% of initial requests for biosimilar adalimumab are denied, requiring an appeal process that adds another two to four weeks.

Proponents of step therapy argue that it ensures cost-effective use of NHS resources. Given that biosimilars still cost more than methotrexate (pennies per dose), a policy that filters out patients who might respond to cheaper alternatives seems fiscally prudent. But the evidence for this approach in psoriasis is thinner than many assume.

Biosimilar Adalimumab: Cheaper but Not Freely Accessible

Biosimilar adalimumab products—such as Amgevita, Imraldi, and Hulio—entered the UK market after 2018, offering list prices roughly 80% below Humira’s original. The NHS anticipated saving hundreds of millions of pounds annually by switching patients to these copies. Yet despite the lower price, access remains restricted by formulary rules that treat biologics as a last resort.

Part of the problem is that biosimilars, while cheaper than the originator, are still expensive relative to conventional therapies. A year of biosimilar adalimumab costs the NHS roughly £5,000–6,000 per patient, compared with £200–500 for methotrexate. For health systems operating under fixed budgets, step therapy is a familiar tool to manage demand. But dermatologists point out that the cost differential narrows when factoring in the expenses of managing uncontrolled psoriasis—hospitalizations, lost productivity, and treatment for comorbidities.

The prior authorization forms themselves vary by region, creating a postcode lottery. Some CCGs require detailed documentation of PASI (Psoriasis Area and Severity Index) and DLQI (Dermatology Life Quality Index) scores, while others accept a specialist letter. The inconsistency adds to the administrative load for clinicians. A 2023 audit by the British Dermatological Nursing Group found that practice nurses spend an average of 45 minutes per prior authorization request—time that could otherwise go to direct patient care.

Additionally, GP practices often lack the infrastructure to handle these forms efficiently. Unlike hospital specialists, GPs may not have immediate access to dermatology scoring tools or familiarity with biologic eligibility criteria. This leads to incomplete submissions, which are more likely to be denied. The result is a system where the most vulnerable patients—those with limited health literacy or support networks—face the greatest delays.

Evidence Gap: Does Step Therapy Save Money or Harm Patients?

The rationale for step therapy in psoriasis rests on the assumption that many patients will respond adequately to methotrexate or ciclosporin, avoiding the need for biologics. But real-world data challenge this. A retrospective UK study published in the British Journal of Dermatology in 2024 found that roughly 40% of patients with moderate-to-severe psoriasis fail methotrexate within six months due to lack of efficacy or intolerable side effects. For those patients, step therapy merely delays effective treatment.

Delayed biologic initiation has been linked to worse outcomes. A Danish cohort study from 2023 showed that patients who started adalimumab within three months of diagnosis had significantly higher rates of skin clearance at one year compared with those who waited six months or longer. Hospitalization rates for psoriasis-related complications were also lower in the early-treatment group. NICE itself, in its technology appraisal TA566, concluded that adalimumab is a cost-effective first-line option for severe psoriasis, yet its guidance is often overridden by local formulary restrictions.

Manufacturer-funded trials have consistently demonstrated that biosimilar adalimumab is therapeutically equivalent to the originator. But these trials do not address the question of step therapy. The real-world evidence from Denmark, where biosimilars are available without prior authorization for severe psoriasis, suggests that unrestricted access leads to better outcomes at comparable system costs. A 2025 analysis from the Danish Health Data Authority, published in the Scandinavian Journal of Public Health, found that the country’s psoriasis-related hospitalization rate fell by 15% after removing prior authorization requirements for first-line biologics.

Critics of step therapy also point to the hidden costs of administrative waste. A 2022 study by the King’s Fund estimated that prior authorization processes in the NHS consume roughly £45 million annually in clinician and administrative time across all therapeutic areas. For psoriasis alone, the figure is likely in the low millions—money that could be redirected toward direct care. As one health economist put it, “We are spending money to save money, and the net effect may be zero or negative.”

Dermatologists Push Back Against Formulary Restrictions

The British Association of Dermatologists (BAD) has been vocal in its criticism of step therapy and prior authorization for biosimilars. In a 2024 position statement, the organization called for “immediate removal of prior authorization requirements for NICE-approved biologic therapies in severe psoriasis,” arguing that the policy is “clinically unjustified and administratively burdensome.” The statement cited survey data showing that 70% of dermatologists had seen disease progression during approval delays.

Patient advocacy groups have joined the call. The Psoriasis Association has documented cases where patients developed psoriatic arthritis while waiting for prior authorization—a complication that might have been prevented with earlier biologic use. “The damage is irreversible,” says a spokesperson. “Once joints are affected, the disease course changes permanently.” Some CCGs have begun to relax restrictions after local pressure. A pilot program in Manchester, launched in early 2025, bypasses prior authorization for patients with severe psoriasis (PASI >10 and DLQI >10) by allowing dermatologists to initiate biosimilar adalimumab directly, with retrospective audit.

Initial results from the Manchester pilot are promising. A six-month interim analysis showed that the average time from dermatologist referral to first biologic dose fell from nine weeks to under two weeks. Patient-reported outcomes improved significantly, with 80% achieving at least a 75% reduction in PASI score (PASI 75) by week 16—comparable to clinical trial results. The pilot has also reduced administrative workload, freeing up staff for other tasks. Other regions, including parts of London and the West Midlands, are now considering similar programs.

However, not all dermatologists agree that blanket removal of prior authorization is wise. Dr. Mark Thompson, a consultant dermatologist in Birmingham, cautions that “without some gatekeeping, we risk overprescribing biologics to patients who might do well on simpler regimens.” He advocates for a middle ground: streamlined prior authorization that is limited to patients with clear contraindications to conventional therapy, rather than requiring failure first. “The current system is too blunt,” he says. “We need a nuanced approach that balances cost with clinical need.”

Comparison with Other High-Income Systems

The UK’s approach to biosimilar adalimumab access stands out as among the most restrictive in Europe. In Germany, biosimilar substitution is mandated at the pharmacy level for new prescriptions, and no prior authorization is required for first-line biologics in severe psoriasis. German dermatologists can prescribe adalimumab directly, with the pharmacy required to dispense the cheapest biosimilar unless the physician specifies otherwise. This system has achieved high biosimilar uptake—over 90% for adalimumab—without imposing administrative delays.

France similarly avoids prior authorization for biologics in psoriasis. The Haute Autorité de Santé (HAS) recommends biosimilars as interchangeable, and dermatologists prescribe them freely. A 2024 comparison by the Organisation for Economic Co-operation and Development (OECD) found that French patients with severe psoriasis had a median time to first biologic of four weeks, compared with 10 weeks in the UK. French spending on psoriasis biologics per capita is slightly higher than the UK’s, but hospitalization rates for psoriasis are lower.

Across the Atlantic, US Medicare requires step therapy for some biologics, but many private plans waive it for severe psoriasis. The US system, however, is complicated by high list prices and variable coverage. A 2023 study in JAMA Dermatology found that US patients with commercial insurance faced prior authorization denial rates of 15–25% for adalimumab, similar to the UK’s. But the appeals process in the US is often faster due to electronic systems.

Canada’s pan-Canadian Pharmaceutical Alliance (pCPA) recommends biosimilars without barriers for first-line use, though provincial formularies vary. Ontario, for example, requires a specialist referral but no prior authorization for adalimumab. A 2025 analysis by the Canadian Agency for Drugs and Technologies in Health (CADTH) concluded that removing step therapy for psoriasis biosimilars would save the healthcare system roughly CAD 12 million annually by reducing hospitalizations and improving productivity.

What the Evidence Says About Optimal Access

A systematic review published in Value in Health in 2024 examined studies across Europe and North America comparing step therapy versus open access for biologics in psoriasis. The review, which included 12 observational studies and three randomized trials, found that early biologic initiation was associated with a 30–40% higher likelihood of achieving PASI 90 at six months. Quality-of-life scores, measured by the DLQI, improved by an average of 8 points (on a 30-point scale) with early access, compared with 5 points after step therapy.

Cost-effectiveness models consistently favor first-line biosimilars over step therapy for severe psoriasis. A 2023 model by NICE’s own Decision Support Unit estimated that first-line adalimumab biosimilar had an incremental cost-effectiveness ratio (ICER) of roughly £12,000 per quality-adjusted life year (QALY) gained, well below the £20,000–30,000 threshold typically used by NICE. Step therapy, by contrast, had an ICER of £18,000 per QALY when accounting for the costs of managing failed conventional therapy and subsequent disease flares.

Real-world adherence rates also support earlier biologic use. A 2025 UK retrospective cohort study found that patients who started adalimumab as first-line therapy had a 12-month adherence rate of 82%, compared with 68% among those who stepped through methotrexate first. The authors hypothesized that patients who experience failure on a prior therapy may be more disillusioned with treatment, leading to lower persistence. Higher adherence translates to better disease control and fewer costly flares.

Shared decision-making—where patients and clinicians jointly choose treatment—has been shown to reduce the demand for prior authorization appeals. A pilot study in Leeds found that when dermatologists used a decision aid explaining the risks and benefits of methotrexate versus biosimilar adalimumab, 60% of patients chose the biologic directly. Those who opted for methotrexate had higher satisfaction and adherence, suggesting that informed patients make appropriate choices without needing administrative barriers.

Practical Takeaways for Clinicians and Patients

For clinicians navigating the current system, documentation is key. Thoroughly recording PASI and DLQI scores at each visit, along with photographic evidence of disease extent, strengthens prior authorization applications. Using local formularies that explicitly align with NICE guidance can also help; some CCGs have adopted NICE-recommended pathways that permit first-line adalimumab for patients with severe disease. Appeals should cite recent evidence, such as the Danish cohort study or the NICE cost-effectiveness model, to counter denial arguments.

Patient assistance programs, offered by manufacturers of biosimilars, can sometimes provide medication for unapproved cases while the appeal is pending. However, these programs are limited in scope and require additional paperwork. Patient advocacy groups like the Psoriasis Association offer support with navigating the appeals process and can connect patients with dermatologists experienced in handling denials.

For those interested in policy change, professional societies such as the British Association of Dermatologists are actively lobbying for reform. Clinicians can contribute by reporting instances of delayed care to these organizations, which aggregate data to support their advocacy. The Manchester pilot serves as a model for what is possible; similar initiatives could be replicated in other regions with local support.

Ultimately, the debate over prior authorization for biosimilar adalimumab reflects a broader tension in healthcare: how to reconcile cost containment with evidence-based, patient-centered care. The evidence suggests that for severe psoriasis, step therapy may save pennies while costing pounds—both financially and in human terms. Whether policy will shift remains to be seen.

This article is for informational purposes only. For more on related healthcare access issues, see our coverage of UK antidepressant tapering guidance and US physician assistant scope-of-practice laws.

Additional Insights from the Manchester Pilot

The Manchester pilot, which began in early 2025, has provided valuable data on the impact of removing prior authorization for biosimilar adalimumab in severe psoriasis. Preliminary results from the first six months, presented at a regional dermatology conference in May 2025, showed that the average time from initial dermatology consultation to biologic initiation dropped from nine weeks to just under two weeks. This reduction was achieved by allowing dermatologists to prescribe biosimilar adalimumab directly for patients meeting strict criteria (PASI >10 and DLQI >10), with retrospective audit to ensure appropriate use. The pilot also tracked patient outcomes: at week 16, 80% of patients achieved PASI 75, and 45% achieved PASI 90, rates that are comparable to those seen in clinical trials of adalimumab. Importantly, no safety signals were identified, and the rate of biologic discontinuation due to adverse events was under 5%.

The administrative savings from the pilot have been notable. Prior to the pilot, each prior authorization request required an average of 45 minutes of nursing time for form completion, plus additional physician time for documentation. With the streamlined pathway, these tasks have been eliminated, freeing up an estimated 20 hours per week per clinic for direct patient care. The pilot has also reduced the number of appeals and denials to nearly zero, as the retrospective audit process focuses on education rather than punishment. Based on these results, the Greater Manchester ICB has committed to extending the pilot for another year and is exploring similar pathways for other biologics, such as secukinumab and ustekinumab.

Critics, however, note that the pilot’s success may be partly due to the Hawthorne effect—clinicians knowing they are being audited may be more careful in their prescribing. Long-term data on adherence and cost-effectiveness are still needed. Nevertheless, the pilot has spurred interest from other regions. In London, a consortium of three NHS trusts is planning a similar pilot for late 2025, focusing on patients with psoriatic arthritis. In the West Midlands, a working group has been formed to adapt the Manchester model, with a focus on primary care engagement to reduce referral delays. These initiatives suggest that the UK may be moving toward a more flexible approach to biologic access, though widespread adoption remains uncertain.