Treatment of refractory adult-onset pityriasis rubra pilaris with TNF-alpha antagonists: a case series

Loss-of-function mutations in Keratin 32 gene disrupt skin immune homeostasis in pityriasis rubra pilaris

Pityriasis rubra pilaris (PRP) is an inflammatory papulosquamous dermatosis, characterized by hyperkeratotic follicular papules and erythematous desquamative plaques. The precise pathogenic mechanism underlying PRP remains incompletely understood. Herein, we conduct a case-control study involving a cohort of 102 patients with sporadic PRP and 800 healthy controls of Han Chinese population and identify significant associations (P = 1.73 × 10-6) between PRP and heterozygous mutations in the Keratin 32 gene (KRT32). KRT32 is found to be predominantly localized in basal keratinocytes and exhibits an inhibitory effect on skin inflammation by antagonizing the NF-κB pathway. Mechanistically, KRT32 binds to NEMO, promoting excessive K48-linked polyubiquitination and NEMO degradation, which hinders IKK complex formation. Conversely, loss-of-function mutations in KRT32 among PRP patients result in NF-κB hyperactivation. Importantly, Krt32 knockout mice exhibit a PRP-like dermatitis phenotype, suggesting compromised anti-inflammatory function of keratinocytes in response to external pro-inflammatory stimuli. This study proposes a role for KRT32 in regulating inflammatory immune responses, with damaging variants in KRT32 being an important driver in PRP development. These findings offer insights into the regulation of skin immune homeostasis by keratin and open up the possibility of using KRT32 as a therapeutic target for PRP.

Use of Biologics in Pityriasis Rubra Pilaris Refractory to First-Line Systemic Therapy: A Systematic Review [Formula: see text]

Pityriasis rubra pilaris (PRP) is an uncommon, inflammatory, papulosquamous skin disease. Treatment of PRP is challenging as the disease is often refractory to conventional therapies, such as retinoids and methotrexate. There has been an increasing number of studies reporting the successful use of biologic therapy in patients with PRP; however, the data on the efficacy and safety are limited. Our objective was to evaluate the existing evidence for utilizing biologics, whether alone or in combination with established systemic therapies, in patients with treatment-resistant PRP. We systematically reviewed evidence within Medline and Pubmed databases between January 1, 2000, to March 31, 2019. Articles consisted of patients diagnosed with PRP who have failed to respond sufficiently to first-line systemic therapies, or who had comorbidities that precluded their use. In total, 363 unique articles were identified, 56 of which were considered relevant to the clinical question. Of the 56 articles highlighted, 35 met the inclusion criteria and were limited to case series and case studies. Therapy with biologics was found to be successful for both monotherapy (81.1% [27/33]) and when used in combination with existing systemic therapies (87.5% [14/16]). The existing evidence suggests that biologics may be regarded as a tool for PRP treatment alone or in combination therapy with existing treatments, although large-scale randomized clinical trials are necessary to better assess their efficacy and safety.

Systemic therapies of pityriasis rubra pilaris: a systematic review

Pityriasis rubra pilaris (PRP) is a rare papulosquamous disorder. Treatment is challenging; the armamentarium consists of topical corticosteroids, phototherapy, classic systemic treatments such as retinoids or immunosuppressive drugs, and most recently biologicals. However, the relative effectiveness of therapies is unclear. Our objective was to review the published literature on systemic treatment of PRP. A systematic review was conducted on PubMed and the Cochrane Library up to 5 September 2017. Studies evaluating any systemic treatments of PRP (except for historical treatments) were included. Overall, 182 studies met the predefined inclusion criteria, and reported on 475 patients and 652 courses of treatment. 42.0 % (225/514) of all patients treated with retinoids achieved an excellent response (isotretinoin: 61.1 % [102/167], etretinate: 47 % [54/115], and acitretin: 24.7 % [43/174]) compared to an excellent response rate of 33.1 % (53/160) with methotrexate. Therapy with biologicals was successful in 51.0 % of patients (71/133) (ustekinumab: 62.5 % [10/16], infliximab: 57.1 % [28/49], etanercept: 53.3 % [16/30], and adalimumab: 46.4 % [13/28]). This review balances effectiveness, side effects, experience, and drug costs in order to suggest a treatment regimen starting with isotretinoin as first-line, methotrexate as second-line and biologicals as third-line treatment for this difficult-to-treat dermatosis.

A Review on Pityriasis Rubra Pilaris

Pityriasis rubra pilaris (PRP) is an idiopathic, papulosquamous inflammatory dermatosis. It is characterized by hyperkeratotic follicular papules coalescing into orange-red scaly plaques, islands of sparing, and palmoplantar keratoderma. PRP can be subdivided into six clinical subtypes according to Griffiths' classification, based on age of onset, disease extent, prognosis, and other associated features. The sixth subtype of PRP occurs in individuals affected by HIV infection, and retroviral screening in all de novo cases of PRP is advised. Other reported associations include various infections, autoimmunity, drugs, and malignancies, although the true significance of these is still unclear. The genetic basis for familial cases, most commonly categorized under the fifth subtype, has been mapped to gain of function mutations in the caspase recruitment domain family, member 14 (CARD14) gene. Treatment of PRP remains a challenge to this day due to a paucity of high-quality evidence. Therapeutic regimens have been guided mostly by case reports and case series, with the mainstay of treatment being oral retinoids. Recently, biologics have emerged as a promising treatment for PRP. We present a review of the clinicopathologic features, pathogenesis, associated disorders, and treatment of PRP, with an emphasis and critical appraisal of the existing literature on the latter.

Biologics for pityriasis rubra pilaris treatment: A review of the literature

Pityriasis rubra pilaris (PRP) is a rare inflammatory papulosquamous skin disease that is often refractory to conventional therapies. The off-label use of biologics, such as anti-tumor necrosis factor, anti-interleukin (IL) 12/IL-23, and anti-IL-17 agents, has been proven successful in the past 2 decades for PRP treatment. Our aim was to analyse the literature for the use of biologics in PRP treatment. We conducted a review by performing PubMed and ClinicalTrials.gov searches. Sixty-eight articles met our selection criteria and are herein discussed. Out of 86 PRP patients, the vast majority were treated with anti-tumor necrosis factor, anti-IL-12/IL-23, or anti-IL-17 biologics, either alone or in combination therapy. A marked-to-complete response was observed in 50%-78%, a partial response in 11%-25%, and no or poor response in 11%-25%. This review has several limitations, including small sample sizes and the lack of shared study design criteria. In some instances, PRP might have resolved spontaneously. Further, the presence of concomitant therapy or the lack of detailed data on previous treatments, makes it difficult to strictly define a therapeutic role per se of specific biologics in PRP. This review shows that biologics may be regarded as a tool for PRP treatment alone or in combination therapy although clinical trials are needed to better assess their efficacy and safety.

[Pityriasis rubra pilaris]

Pityriasis rubra pilaris is a rare heterogeneous dermatosis associating three clinical signs to different degrees: follicular corneal papules, reddish-orange palmoplantar keratoderma and erythematosquamous lesions that may in some cases be very extensive, interspersed with patches of healthy skin. The aetiology is unclear, and in most cases, the trigger factors consist of trauma or infection, probably in subjects with an existing predisposition. In other cases, the condition is associated with immunological disorders or, in familial cases, genetic keratinisation abnormalities similar to ichthyosis. Given the widely varying signs, several classifications have been proposed, based on clinical criteria and outcomes. The outcome varies in accordance with the clinical forms involved. Therapeutic approaches are poorly qualified and there have been no clinical trials due to the rarity of the disease. However, the best results appear to have been obtained using oral retinoids, with second-line therapy comprising methotrexate and cyclosporine. The landscape of therapeutic strategy seems to be changing with the advent of new anti-tumour necrosis factor and anti-interleukin-12/23 antibodies.

Management of refractory pityriasis rubra pilaris: challenges and solutions

Pityriasis rubra pilaris (PRP) is a rare chronic inflammatory papulosquamous skin disease. Its clinical presentation and evolution is very variable. The most frequent clinical features are follicular papules, progressing to yellow-orange erythroderma with round small areas of normal skin and the well-demarcated palmoplantar keratoderma. Actually, six different types of PRP have been described based on clinical characteristics, age of onset, and prognosis. The pathogenesis is still unknown, and treatment can be challenging. Available treatments are mainly based on case reports or case series of clinical experience because no controlled randomized trials have never been performed because of the rarity of the condition. Traditional systemic treatment consists in retinoids, which are actually considered as first-line therapy, but refractory cases that do not respond or relapse after drug interruption do exist. In recent years, numerous reports have demonstrated the efficacy of new agents such as biological drugs. This article is an overview on available therapeutic options, in particular for refractory forms of PRP.

Ustekinumab treatment of pityriasis rubra pilaris: A report of five cases

Pityriasis rubra pilaris (PRP) is a rare, chronic, inflammatory skin disease of unknown etiology. Patients refractory to conventional therapies have been treated successfully with biologic drugs such as anti-tumor necrosis factor agents. Recently, a role of the interleukin-23/T-helper 17 axis in PRP has been described. Our objective was to assess the effectiveness of ustekinumab in five patients with adult-onset PRP refractory to conventional therapies. In the present study, four patients had type I and one patient type II adult-onset PRP. They were treated with three s.c. doses of ustekinumab at weeks 0, 4 and 16. Clinical response was evaluated monthly during treatment up to a 15-month follow-up period. All patients promptly showed a decrease in erythema, follicular hyperkeratosis and scaling. After three injections, complete remission of skin lesions was achieved in four out of five cases and a significant clinical improvement was shown in one case. To the best of our knowledge, this is the largest case series reported on ustekinumab treatment in PRP. Our results, in addition to previous studies from other groups, suggest that ustekinumab may be a possible first-line treatment for PRP patients refractory to conventional therapies.

Refractory pityriasis rubra pilaris treated with etanercept, adalimumab, or ustekinumab: A retrospective investigation

Pityriasis rubra pilaris (PRP) is a rare, difficult to treat papulosquamous disorder that responds variably to retinoids and immunosuppression. Successful use of biologics for treating PRP has been described in the literature by case reports and a limited number of case series. To provide additional data, we retrospectively analyzed cases of PRP treated with biologics at our institution. We identified seven patients with a clear diagnosis of PRP treated with adalimumab, etanercept, and/or ustekinumab at our institution from January 1, 2014 to April 1, 2017. Six of seven patients had type I, adult acquired PRP, and one had type V atypical juvenile PRP. In response to tumor necrosis factor (TNF)-α inhibition, two patients had marked responses (>75% improvement in involved body surface area), while three patients failed to show any improvement on a TNF-α inhibitor. In two cases of PRP refractory to TNF-α inhibition, ustekinumab resulted in a partial response (<75% improvement) in one patient and no response in the other. Compared to other published data, our cohort was substantially more resistant to treatment with biologics, a finding which may provide valuable perspective for dermatologists managing refractory PRP in the future.

Biologics in dermatology: an integrated review

The advent of biologics in dermatologic treatment armentarium has added refreshing dimensions, for it is a major breakthrough. Several agents are now available for use. It is therefore imperative to succinctly comprehend their pharmacokinetics for their apt use. A concerted endeavor has been made to delve on this subject. The major groups of biologics have been covered and include: Drugs acting against TNF-α, Alefacept, Ustekinumab, Rituximab, IVIG and Omalizumab. The relevant pharmacokinetic characteristics have been detailed. Their respective label (approved) and off-label (unapproved) indications have been defined, highlighting their dosage protocol, availability and mode of administration. The evidence level of each indication has also been discussed to apprise the clinician of their current and prospective uses. Individual anti-TNF drugs are not identical in their actions and often one is superior to the other in a particular disease. Hence, the section on anti-TNF agents mentions the literature on each drug separately, and not as a group. The limitations for their use have also been clearly brought out.

[Off-label use of infliximab]

Tumor necrosis factor α (TNFα) is a pro-inflammatory cytokine and a key mediator of inflammation. Several TNFα antagonists have been used therapeutically. One of them, infliximab, is a chimeric monoclonal antibody with anti-TNFα activity. Numerous studies have shown TNFα antagonists to be effective in treating psoriasis--particularly severe resistant forms--and arthritis. Additionally, several case reports and studies showing the effects of TNFα on new dermatologic indications have been published. The intention of this review is to summarize the new off-label uses of infliximab according to published data.

Acute cutaneous graft-versus-host disease resembling type II (atypical adult) pityriasis rubra pilaris

We present a case of cutaneous acute graft-versus-host disease (aGVHD) with confluent erythematous perifollicular hyperkeratosis and ichthyosiform scale in the clinical pattern of type II (atypical adult) pityriasis rubra pilaris (PRP), which developed 26 days after allogeneic peripheral blood stem cell transplant. Skin histology confirmed features of both aGVHD and PRP. The skin lesions were refractory to oral prednisolone and cyclosporine and only partially responsive to a combination of i.v. methylprednisolone, oral tacrolimus, oral mycophenolate mofetil, and infusions of anti-thymocyte globulin and the tumour necrosis factor-α inhibitor, etanercept.

Pityriasis rubra pilaris with the concomitant Leser — Trelat syndrome

The authors describe a rare case of pityriasis rubra pilaris with the concomitant Leser — Trelat syndrome. Taking into consideration contra-indications for UV therapy, Neotigason (acitretin) was prescribed in the dose of 25 mg a day. Nearly absolute regression of eruptions characteristic of pityriasis rubra pilaris and multiple seborrheic keratomas was observed.

Biologics in dermatology

Skin and subcutaneous diseases affect millions of people worldwide, causing significant morbidity. Biologics are becoming increasingly useful for the treatment of many skin diseases, particularly as alternatives for patients who have failed to tolerate or respond to conventional systemic therapies. Biological therapies provide a targeted approach to treatment through interaction with specific components of the underlying immune and inflammatory disease processes. This review article examines the increasing evidence base for biologics in dermatology, including well-established treatments and novel agents.

Immunotherapies in dermatologic disorders

Treatment modalities and therapeutic response experience support the use of immunotherapy in the treatment of many diseases in all fields of medicine. The aim of this article is to conduct and present a review of literature on the use of immunotherapy in the treatment of skin diseases analyzing scientific literature available up to January 2012. Studies that presented evidence-based data were selected. The article discusses how blocking or reverting the effect of a specific immunologic disequilibrium can treat dermatoses and intends to transfer a large amount of immunotherapy knowledge into a historical perspective for physicians naive to immunotherapy practices.

Tumor necrosis factor biologics beyond psoriasis in dermatology

INTRODUCTION

TNF-α is a cytokine essential for immune response and its receptors has been shown to be dysregulated in a variety of diseases including psoriasis vulgaris. There are a number of TNF-α inhibitors approved for psoriasis, however there is a growing body of literature supporting their use in a wide variety of dermatological conditions.

AREAS COVERED

The use of biologic TNF-α antagonists in conditions for which they have not yet been approved by the FDA ('off-label' uses) and the literature that supports the most appropriate agents and conditions for use. A PubMed/MEDLINE search was performed with the keywords 'TNFα antagonist', 'biologic therapy', 'off-label' and 'unapproved'. The list of references and citing articles of the articles retrieved were also used as sources. This complete list was evaluated for inclusion, based on relevance to the proposed goal of this review.

EXPERT OPINION

There are a large number of conditions for which biologic antagonists of TNFα are effective, beyond those already approved by the FDA. The various agents vary in their efficacy in treatment, with infliximab consistently the most effective, particularly in granulomatous diseases. Although effectiveness varies among these conditions, biologic antagonists of TNF-α are promising for the treatment of these diseases.