Psoriasis, PsA, and Pregnancy: Tailoring Treatment With Increasing Data

With an average age of diagnosis of 28 years, and one of two incidence peaks occurring at 15-30 years, psoriasis affects many women in the midst of their reproductive years. The prospect of pregnancy – or the reality of a surprise pregnancy – drives questions about heritability of the disease in offspring, the impact of the disease on pregnancy outcomes and breastfeeding, and how to best balance risks of treatments with risks of uncontrolled psoriasis and/or psoriatic arthritis (PsA).

While answers to these questions are not always clear, discussions about pregnancy and psoriasis management "shouldn't be scary," said Jenny E. Murase, MD, a dermatologist who speaks and writes widely about her research and experience with psoriasis and pregnancy. "We have access to information and data and educational resources to [work with] and reassure our patients – we just need to use it. Right now, there's unnecessary suffering [with some patients unnecessarily stopping all treatment]."

Much has been learned in the past 2 decades about the course of psoriasis in pregnancy, and pregnancy outcomes data on the safety of biologics during pregnancy are increasingly emerging – particularly for tumor necrosis factor (TNF)–alpha inhibitors.

Ideally, since half of all pregnancies are unplanned, the implications of therapeutic options should be discussed with all women with psoriasis who are of reproductive age, whether they are sexually active or not. "The onus is on us to make sure that we're considering the possibility [that our patient] could become pregnant without consulting us first," said Dr. Murase, associate professor of dermatology at the University of California, San Francisco, and director of medical consultative dermatology for the Palo Alto Foundation Medical Group in Mountain View, Calif.

Lisa R. Sammaritano, MD, associate professor of clinical medicine at Weill Cornell Medicine and a rheumatologist at the Hospital for Special Surgery, both in New York, urges similar attention for PsA. "Pregnancy is best planned while patients have quiescent disease on pregnancy-compatible medications," she said. "We encourage [more] rheumatologists to be actively involved in pregnancy planning [in order] to guide therapy."

The Impact of Estrogen

Dr. Murase was inspired to study psoriasis and pregnancy in part by a patient she met as a medical student. "She had severe psoriasis covering her body, and she said that the only times her psoriasis cleared was during her three pregnancies," Dr. Murase recalled. "I wondered: What about the pregnancies resulted in such a substantial reduction of her psoriasis?"

She subsequently led a study, published in 2005, of 47 pregnant and 27 nonpregnant patients with psoriasis. More than half of the patients – 55% – reported improvements in their psoriasis during pregnancy, 21% reported no change, and 23% reported worsening. Among the 16 patients who had 10% or greater psoriatic body surface area (BSA) involvement and reported improvements, lesions decreased by 84%.

In the postpartum period, only 9% reported improvement, 26% reported no change, and 65% reported worsening. The increased BSA values observed 6 weeks postpartum did not exceed those of the first trimester, suggesting a return to the patients' baseline status.

Earlier and smaller retrospective studies had also shown that approximately half of patients improve during pregnancy, and it was believed that progesterone was most likely responsible for this improvement. Dr. Murase's study moved the needle in that it examined BSA in pregnancy and the postpartum period. It also turned the spotlight on estrogen: Patients who had higher levels of improvement also had higher levels of estradiol, estrone, and the ratio of estrogen to progesterone. However, there was no correlation between psoriatic change and levels of progesterone.

To promote fetal survival, pregnancy triggers a shift from Th1 cell–mediated immunity – and Th17 immunity – to Th2 immunity. While there's no proof of a causative effect, increased estrogen appears to play a role in this shift and in the reduced production of Th1 and Th17 cytokines. Psoriasis is believed to be primarily a Th17-mediated disease, with some Th1 involvement, so this down-regulation can result in improved disease status, Dr. Murase said. (A host of other autoimmune diseases categorized as Th1 mediated similarly tend to improve during pregnancy, she added.)

Information on the effect of pregnancy on PsA is "conflicting," Dr. Sammaritano said. "Some [of a limited number of studies] suggest a beneficial effect as is generally seen for rheumatoid arthritis. Others, however, have found an increased risk of disease activity during pregnancy ... It may be that psoriatic arthritis can be quite variable from patient to patient in its clinical presentation."

At least one study, Dr. Sammaritano added, "has shown that the arthritis in pregnancy patients with PsA did not improve, compared to control nonpregnant patients, while the psoriasis rash did improve."

The mixed findings don't surprise Dr. Murase. "It harder to quantify joint disease in general," she said. "And during pregnancy, physiologic changes relating to the pregnancy itself can cause discomfort – your joints ache. The numbers [of improved] cases aren't as high with PsA, but it's a more complex question."

In the postpartum period, however, research findings "all suggest an increased risk of flare" of PsA, Dr. Sammaritano said, just as with psoriasis.

Assessing Risk of Treatment

Understanding the immunologic effects of pregnancy on psoriasis and PsA – and appreciating the concept of a hormonal component – is an important part of treatment decision making. So is understanding pregnancy outcomes data.

Researchers have looked at a host of pregnancy outcomes – including congenital malformations, preterm birth, spontaneous abortion, low birth weight, macrosomia, and gestational diabetes and hypertension – in women with psoriasis or psoriasis/PsA, compared with control groups. Some studies have suggested a link between disease activity and pregnancy complications or adverse pregnancy outcomes, "just as a result of having moderate to severe disease," while others have found no evidence of increased risk, Dr. Murase said.

"It's a bit unclear and a difficult question to answer; it depends on what study you look at and what data you believe. It would be nice to have some clarity, but basically the jury is still out," said Dr. Murase, who, with coauthors Alice B. Gottlieb, MD, PhD, of the department of dermatology at the Icahn School of Medicine at Mount Sinai, New York, and Caitriona Ryan, MD, of the Blackrock Clinic and Charles Institute of Dermatology, University College Dublin, discussed the pregnancy outcomes data in a recently published review of psoriasis in women.

"In my opinion, because we have therapies that are so low risk and well tolerated, it's better to make sure that the inflammatory cascade and inflammation created by psoriasis is under control," she said. "So whether or not the pregnancy itself causes the patient to go into remission, or whether you have to use therapy to help the patient stay in remission, it's important to control the inflammation."

Contraindicated in pregnancy are oral psoralen, methotrexate, and acitretin, the latter of which should be avoided for several years before pregnancy and "therefore shouldn't be used in a woman of childbearing age," said Dr. Murase. Methotrexate, said Dr. Sammaritano, should generally be stopped 1-3 months prior to conception.

For psoriasis, the therapy that's "classically considered the safest in pregnancy is UVB light therapy, specifically the 300-nm wavelength of light, which works really well as an anti-inflammatory," Dr. Murase said. Because of the potential for maternal folate degradation with phototherapy and the long-known association of folate deficiency with neural tube defects, women of childbearing age who are receiving light therapy should take daily folic acid supplementation. (She prescribes a daily prenatal vitamin containing at least 1 mg of folic acid for women who are utilizing light therapy.)

Many topical agents can be used during pregnancy, Dr. Murase said. Topical corticosteroids, she noted, have the most safety-affirming data of any topical medication.

Regarding oral therapies, Dr. Murase recommends against the use of apremilast (Otezla) for her patients. "It's not contraindicated, but the animal studies don't look promising, so I don't use that one in women of childbearing age just in case. There's just very little data to support the safety of this medication [in pregnancy]."

There are no therapeutic guidelines in the United States for guiding the management of psoriasis in women who are considering pregnancy. In 2012, the medical board of the National Psoriasis Foundation published a review of treatment options for psoriasis in pregnant or lactating women, the "closest thing to guidelines that we've had," said Dr. Murase. (Now almost a decade old, the review addresses TNF inhibitors but does not cover the anti-interleukin agents more recently approved for moderate to severe psoriasis and PsA.)

For treating PsA, rheumatologists now have the American College of Rheumatology's first guideline for the management of reproductive health in rheumatic and musculoskeletal diseases to reference. The 2020 guideline does not address PsA specifically, but its section on pregnancy and lactation includes recommendations on biologic and other therapies used to treat the disease.

Guidelines aside, physician-patient discussions over drug safety have the potential to be much more meaningful now that drug labels offer clinical summaries, data, and risk summaries regarding potential use in pregnancy. The labels have "more of a narrative, which is a more useful way to counsel patients and make risk-benefit decisions" than the former system of five-letter categories, said Dr. Murase. (The changes were made per the Pregnancy and Lactation Labeling Rule of 2015.)

MothertoBaby, a service of the nonprofit Organization of Teratology Information Specialists, also provides good evidence-based information to physicians and mothers, Dr. Sammaritano noted.

The Use of Biologic Therapies

In a 2017 review of biologic safety for patients with psoriasis during pregnancy, Alexa B. Kimball, MD, MPH, professor of dermatology at Harvard Medical School, Boston; Martina L. Porter, MD, currently with the department of dermatology at Beth Israel Deaconess Medical Center, Boston; and Stephen J. Lockwood, MD, MPH, of the department of dermatology at Harvard Medical School, concluded that an increasing body of literature suggests that biologic agents can be used during pregnancy and breastfeeding. Anti-TNF agents "should be considered over IL-12/23 and IL-17 inhibitors due to the increased availability of long-term data," they wrote.

"In general," said Dr. Murase, "there's more and more data coming out from gastroenterology and rheumatology to reassure patients and prescribing physicians that the TNF-blocker class is likely safe to use in pregnancy," particularly during the first trimester and early second trimester, when the transport of maternal antibodies across the placenta is "essentially nonexistent." In the third trimester, the active transport of IgG antibodies increases rapidly.

If possible, said Dr. Sammaritano, who served as lead author of the ACR's reproductive health guideline, TNF inhibitors "will be stopped prior to the third trimester to avoid [the possibility of] high drug levels in the infant at birth, which raises concern for immunosuppression in the newborn. If disease is very active, however, they can be continued throughout the pregnancy."

The TNF inhibitor certolizumab pegol (Cimzia) has the advantage of being transported only minimally across the placenta, if at all, she and Dr. Murase both explained. "To be actively carried across, antibodies need what's called an Fc region for the placenta to grab onto," Dr. Murase said. Certolizumab – a pegylated anti–binding fragment antibody – lacks this Fc region.

Two recent studies – CRIB and a UCB Pharma safety database analysis – showed "essentially no medication crossing – there were barely detectable levels," Dr. Murase said. Certolizumab's label contains this information and other clinical trial data as well as findings from safety database analyses/surveillance registries.

"Before we had much data for the biologics, I'd advise transitioning patients to light therapy from their biologics and a lot of times their psoriasis would improve, but it was more of a dance," she said. "Now we tend to look at [certolizumab] when they're of childbearing age and keep them on the treatment. I know that the baby is not being immunosuppressed."

Consideration of the use of certolizumab when treatment with biologic agents is required throughout the pregnancy is a recommendation included in Dr. Kimball's 2017 review.

As newer anti-interleukin agents – the IL-12/23 and IL-17 inhibitors – play a growing role in the treatment of psoriasis and PsA, questions loom about their safety profile. Dr. Murase and Dr. Sammaritano are waiting for more data. "In general," Dr. Sammaritano said, "we recommend stopping them at the time pregnancy is detected, based on a lack of data at this time."

Small-molecule drugs are also less well studied, she noted. "Because of their low molecular weight, we anticipate they will easily cross the placenta, so we recommend avoiding use during pregnancy until more information is available."

Postpartum Care

The good news, both experts say, is that the vast majority of medications, including biologics, are safe to use during breastfeeding. Methotrexate should be avoided, Dr. Sammaritano pointed out, and the impact of novel small-molecule therapies on breast milk has not been studied.

In her 2019 review of psoriasis in women, Dr. Murase and coauthors wrote that too many dermatologists believe that breastfeeding women should either not be on biologics or are uncertain about biologic use during breastfeeding. However, "biologics are considered compatible for use while breastfeeding due to their large molecular size and the proteolytic environment in the neonatal gastrointestinal tract," they added.

Counseling and support for breastfeeding is especially important for women with psoriasis, Dr. Murase emphasized. "Breastfeeding is very traumatizing to the skin, and psoriasis can form in skin that's injured. I have my patients set up an office visit very soon after the pregnancy to make sure they're doing alright with their breastfeeding and that they're coating their nipple area with some type of moisturizer and keeping the health of their nipples in good shape."

Timely reviews of therapy and adjustments are also a priority, she said. "We need to prepare for 6 weeks post partum" when psoriasis will often flare without treatment.

Dr. Murase disclosed that she is a consultant for Dermira, UCB Pharma, Sanofi, Ferndale, and Regeneron. She is also coeditor in chief of the International Journal of Women's Dermatology. Dr. Sammaritano reported that she has no disclosures relating to the treatment of PsA.

This article originally appeared on MDedge.com, part of the Medscape Professional Network.

Medscape Medical News © 2020 

Cite this: Psoriasis, PsA, and Pregnancy: Tailoring Treatment With Increasing Data - Medscape - Sep 03, 2020.