Pharmacokinetics of single- and multiple-dose roflumilast: an open-label, three-way crossover study in healthy Chinese volunteers

A Review of Topical Roflumilast for the Treatment of Plaque Psoriasis

OBJECTIVE

This article reviews clinical trials to assess the efficacy, safety, and clinical application of once-daily roflumilast 0.3% cream for the treatment of plaque psoriasis.

DATA SOURCES

A systematic review of the literature was performed using the terms roflumilast OR Zoryve OR ARQ-151 in MEDLINE (PubMed) and EMBASE databases between January 2012 and October 2022. Bibliographies and the ClinicalTrials.gov website were also searched to identify further studies.

STUDY SELECTION AND DATA EXTRACTION

Studies written in English and relevant to pharmacology, clinical trials, and safety were considered for inclusion.

DATA SYNTHESIS

In two 8-week phase III clinical trials, disease severity as assessed by a score of "clear" or "almost clear" and a 2-point improvement on Investigator Global Assessment (IGA) was 42.4% and 37.5% at week 8 in DERMIS-1 and DERMIS-2, respectively, compared to 6.1% and 6.9% in the control groups. In the 52-week phase III trial, treatment success rates for plaque psoriasis and intertriginous psoriasis were similar to the 8-week data with 45% of patients in the treatment group were evaluated as an IGA of "clear" or "almost clear" at week 52.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE IN COMPARISON TO EXISTING DRUGS

Roflumilast is a new US Food and Drug Administration (FDA)-approved topical phosphodiesterase inhibitor that shows promise for the treatment of mild-severe plaque psoriasis. It is an effective and safe topical nonsteroidal alternative to currently available topical corticosteroids, but there are currently no comparative studies with other psoriasis treatments.

CONCLUSION

Roflumilast is effective and safe for the treatment of plaque psoriasis and intertriginous psoriasis. Future trials should compare its efficacy and tolerability with that of the older, clinically established topical corticosteroids. Prohibitive factors may include limited patient adherence to topical treatments and cost.

Pre-Clinical Assessment of Roflumilast Therapy in a Thoracic Model of Spinal Cord Injury

The failure of axons to regenerate after a spinal cord injury (SCI) remains one of the greatest challenges in neuroscience. The initial mechanical trauma is followed by a secondary injury cascade, creating a hostile microenvironment, which not only is not permissive to regeneration but also leads to further damage. One of the most promising approaches for promoting axonal regeneration is to maintain the levels of cyclic adenosine monophosphate (cAMP), specifically by a phosphodiesterase-4 (PDE4) inhibitor expressed in neural tissues. Therefore, in our study, we evaluated the therapeutic effect of an FDA-approved PDE4 inhibitor, Roflumilast (Rof), in a thoracic contusion rat model. Results indicate that the treatment was effective in promoting functional recovery. Rof-treated animals showed improvements in both gross and fine motor function. Eight weeks post-injury, the animals significantly recovered by achieving occasional weight-supported plantar steps. Histological assessment revealed a significant decrease in cavity size, less reactive microglia, as well as higher axonal regeneration in treated animals. Molecular analysis revealed that IL-10 and IL-13 levels, as well as VEGF, were increased in the serum of Rof-treated animals. Overall, Roflumilast promotes functional recovery and supports neuroregeneration in a severe thoracic contusion injury model and may be important in SCI treatment.

A Single-center, Open-label, Parallel Control Study Comparing the Pharmacokinetics and Safety of a Single Oral Dose of Roflumilast and Its Active Metabolite Roflumilast N-oxide in Healthy Chinese and Caucasian Volunteers

Roflumilast is a phosphodiesterase-4 inhibitor which treats chronic obstructive pulmonary disease (COPD). Roflumilast N-oxide is the major metabolite of roflumilast with a similar mechanism of action to roflumilast. Although racial differences in roflumilast drug disposition have been observed, the necessity of dose adjustment is subject to debate. This study compares the pharmacokinetics of a single 500 μg dose of roflumilast in healthy Chinese and Caucasian subjects under uniform conditions. Chinese subjects were found to have longer t_1/2 and higher AUC_0-t and C_max than Caucasian subjects. The point estimates on the geometric mean of AUC_0-t in Chinese subjects were 22% higher for roflumilast and 46% higher for roflumilast N-oxide. Point estimates on the geometric mean of C_max were 9% and 24% higher for roflumilast and roflumilast N-oxide, respectively. Total phosphodiesterase-4 (PDE4) inhibitory (tPDE4i) activity, a theoretical parameter that describes the combined contribution to PDE4 inhibitory activity of roflumilast and roflumilast N-oxide, was 44% higher in Chinese subjects than in Caucasian subjects. With about a 10-fold higher plasma AUC compared to the parent roflumilast and a much longer observed half-life, roflumilast N-oxide has been estimated to contribute about 90% of tPDE4i, with 10% attributed to the parent compound roflumilast. Following body weight normalization, these figures were lower but remained significant. Safety analysis showed signs of reduced tolerance or different pharmacodynamic response to roflumilast in Chinese recipients than in Caucasians. Our results suggest that Chinese patients should receive a dose of roflumilast lower than 500 μg daily during future clinical trials.

Sex differences in COPD management

Introduction: A growing body of evidence indicates that prevalence of chronic obstructive pulmonary disease (COPD) has been increasing more rapidly among women compared to men, but the available data on the differences between the sexes in the responses to the various COPD therapies are still scarce.Areas covered: The aim of this narrative review is to provide an overview of current knowledge on sex differences in COPD management.Expert opinion: There is no solid evidence of sex differences in response to usual COPD treatments but there are sex-related differences in management of patients with a clinical diagnosis of COPD. It is difficult to explain the reason for these differences, but most likely they are due to local prescribing habits, rather than solid scientific reasons. However, there are also signals of different sex-related responses, the qualification and quantification of which is difficult with the information currently available. These signals should lead to the inclusion of more women in clinical trials, but also to the design of prospective clinical studies to assess the possible differences linked to sex in COPD treatment responses, whose identification is an important step toward the definition of personalized COPD therapy.

Simultaneous quantification and pharmacokinetic evaluation of roflumilast and its N-oxide in cynomolgus monkey plasma by LC-MS/MS method

Roflumilast (ROF), a nonsteroidal anti-inflammatory drug, has successfully been used to treat systemic and pulmonary inflammation associated with chronic obstructive pulmonary disease. To evaluate its pharmacokinetics in monkeys, a sensitive, rapid and reliable liquid chromatography with tandem mass spectrometry (LC-MS/MS) method was developed for the simultaneous determination of ROF and its N-oxide metabolite (RNO). The mobile phase contained 0.1% formic acid aqueous solution (A) and 0.1% formic acid acetonitrile solution (B). All monkey plasma samples were pretreated using protein precipitation with methanol-acetonitrile (50:50, v/v) in 50 μl plasma samples. Chromatographic separation was performed with mass spectral acquisition performed in positive electrospray ionization, utilizing multiple reaction monitoring. This method was successfully applied to a pharmacokinetic study in cynomolgus monkeys. Following administration of a single oral dose of 1 mg/kg ROF in monkeys, pharmacokinetic data for ROF and RNO was reported for the first time. After oral administration, ROF was rapidly absorbed and metabolized to its metabolite RNO. The mean area under the curve value of RNO was ~13 times larger than that of ROF, suggesting that most ROF was metabolized to RNO in cynomolgus monkeys.