Psoriasis Expert Shares Strategies for Treatment Modification

Photo Credit: Outflow Designs

At the 2025 Winter Clinical Dermatology Conference, Ronald Vender, MD, discussed a treatment goal algorithm for patients with psoriasis.

The treatment goal algorithm involves the following modification strategies:

• Increasing the dose;
• Reducing dose intervals;
• Adding a topical;
• Adding another systemic; and
• Switching the drug.

Why Switch Therapies?

For several reasons, clinicians and patients may consider switching drugs rather than adjusting doses or adding other therapies.

One reason is primary failure, which involves a lack of initial efficacy and minimal improvement over the first six months of treatment. A small percentage of patients experience primary failure after starting biologics.

“In the past, [primary failure] meant PASI75, and now it’s probably PASI90. In the future, it may be PASI100,” Dr. Vender said.

The patient may also experience secondary failure, which occurs when the drug works initially but loses efficacy over time. Patients are at higher risk for secondary failure if they have previous biologic failures, psoriatic arthritis, issues with adherence, are overweight, or have comorbidities like diabetes, hypertension, or cardiometabolic disease. Dr. Vender noted that clinicians may consider increasing the dose or decreasing intervals between treatments to reduce the likelihood of secondary failure.

Adverse events may also be a factor, but they are typically “a very uncommon reason to switch,” Dr. Vender said. Alternatively, the patient may want to try a different drug, or the insurance company may require a switch for continued coverage.

Is a Washout Period Needed?

A washout period can ensure the patient does not experience adverse events from two medications simultaneously. However, the session highlighted that the risk for psoriasis flares was greater than the risk for adverse effects when overlapping drugs.

“You don’t want the psoriasis to come back,” Dr. Vender said.

Some argue that there may be an increased risk for infection without an adequate washout period, but data are limited to support this theory.

“We don’t need a washout period,” Dr. Vender said. “Some people say you do because you don’t want to overlap the drugs in terms of immunosuppression. We don’t get that because they’re immunomodulatory.”

Dr. Vender advised that clinicians forego a washout period, switch drugs at the next scheduled dose of the failed biologic, and then use standard induction dosing followed by standard maintenance dosing.