Roflumilast tópico y oral en dermatología. Una revisión narrativa / Topical and Oral Roflumilast in Dermatology: A Narrative Review

Roflumilast es un inhibidor de la fosfodiesterasa-4 aprobado de forma oral para la prevención de exacerbaciones en pacientes con enfermedad pulmonar obstructiva crónica y fenotipo de bronquitis crónica. En dermatología, el roflumilast tópico está aprobado por la Food and Drug Administration en psoriasis en placas y dermatitis seborreica leve/moderada. En cuanto a su uso fuera de indicación, hemos encontrado un ensayo clínico que avala la utilidad del roflumilast oral en psoriasis, así como pequeñas series de casos o casos clínicos aislados en hidradenitis supurativa, aftosis oral recurrente, eccema numular, liquen plano y enfermedad de Behçet. Su perfil de seguridad es favorable, similar al del apremilast, y su coste es considerablemente inferior a los de los fármacos de nueva generación, o incluso al de algunos inmunosupresores clásicos. Presentamos una revisión de roflumilast tópico y oral, en términos de farmacocinética y farmacodinámica, efectos adversos, usos dermatológicos aprobados y fuera de indicación. Roflumilast es un agente prometedor en dermatología.(AU)

Oral roflumilast is a phosphodiesterase-4 inhibitor approved for the prevention of exacerbations of chronic obstructive pulmonary disease and chronic bronchitis. In dermatology, topical roflumilast is authorized by the US Food and Drug Administration for the treatment of plaque psoriasis and mild to moderate seborrheic dermatitis. Several studies have described the off-label use of roflumilast in dermatology, including a randomized controlled trial showing its usefulness in the treatment of psoriasis; case reports and small series have also reported successful outcomes in hidradenitis suppurativa, recurrent oral aphthosis, nummular eczema, lichen planus, and Behçet disease. Roflumilast has a favorable safety profile, similar to that of apremilast, and it is considerably cheaper than new generation drugs and even some conventional immunosuppressants. We review the pharmacokinetics and pharmacodynamics of topical and oral roflumilast and discuss potential adverse effects and both approved and off-label uses in dermatology. Roflumilast is a promising agent to consider.(AU)

[Translated aticle] Topical and Oral Roflumilast in Dermatology: A Narrative Review / Roflumilast tópico y oral endermatología. Una revisión narrativa

Roflumilast es un inhibidor de la fosfodiesterasa-4 aprobado de forma oral para la prevención de exacerbaciones en pacientes con enfermedad pulmonar obstructiva crónica y fenotipo de bronquitis crónica. En dermatología, el roflumilast tópico está aprobado por la Food and Drug Administration en psoriasis en placas y dermatitis seborreica leve/moderada. En cuanto a su uso fuera de indicación, hemos encontrado un ensayo clínico que avala la utilidad del roflumilast oral en psoriasis, así como pequeñas series de casos o casos clínicos aislados en hidradenitis supurativa, aftosis oral recurrente, eccema numular, liquen plano y enfermedad de Behçet. Su perfil de seguridad es favorable, similar al del apremilast, y su coste es considerablemente inferior a los de los fármacos de nueva generación, o incluso al de algunos inmunosupresores clásicos. Presentamos una revisión de roflumilast tópico y oral, en términos de farmacocinética y farmacodinámica, efectos adversos, usos dermatológicos aprobados y fuera de indicación. Roflumilast es un agente prometedor en dermatología.(AU)

Oral roflumilast is a phosphodiesterase-4 inhibitor approved for the prevention of exacerbations of chronic obstructive pulmonary disease and chronic bronchitis. In dermatology, topical roflumilast is authorized by the US Food and Drug Administration for the treatment of plaque psoriasis and mild to moderate seborrheic dermatitis. Several studies have described the off-label use of roflumilast in dermatology, including a randomized controlled trial showing its usefulness in the treatment of psoriasis; case reports and small series have also reported successful outcomes in hidradenitis suppurativa, recurrent oral aphthosis, nummular eczema, lichen planus, and Behçet disease. Roflumilast has a favorable safety profile, similar to that of apremilast, and it is considerably cheaper than new generation drugs and even some conventional immunosuppressants. We review the pharmacokinetics and pharmacodynamics of topical and oral roflumilast and discuss potential adverse effects and both approved and off-label uses in dermatology. Roflumilast is a promising agent to consider.(AU)

Orismilast for the treatment of mild to severe hidradenitis suppurativa: Week 16 data from OSIRIS, a Phase 2a, open-label, single-centre, single-arm, dose-finding clinical trial.

BACKGROUND: Hidradenitis suppurativa (HS) is a disease with an unmet need for treatment. OBJECTIVE: To examine tolerability, safety and efficacy of oral phosphodiesterase-4 (PDE4) inhibitior orismilast 10-40 mg twice daily (BID) in HS. METHODS: A Phase 2a, single-arm, single-centre, open-label, 16-week trial in HS patients. Adjustments in maximal dose and titration were allowed, to improve tolerability, dividing the study population in two groups who completed and discontinued 16 weeks of treatment. Descriptive statistics were applied to efficacy data from patients who completed treatment and patients who discontinued treatment prematurely. A last-observation-carried-forward (LOCF) approach was used for patients who discontinued treatment. The primary endpoint was percent change in the total number of abscesses and nodules (AN-count) at Week 16, with the HS Clinical Response with a 50% reduction in the AN-count (HiSCR50) as key secondary endpoint. RESULTS: Of the 20 patients included, 9 completed 16 weeks of treatment and 11 discontinued treatment prematurely. The mean AN-count was reduced with 33.1% in patients who completed treatment and with 12.0% in patients who discontinued. HiSCR50 was achieved by 67.0% and 27.0% of patients who completed and discontinued treatment, respectively. Most adverse events were mild to moderate. CONCLUSIONS: Oral orismilast demonstrated a dose-dependent tolerability, with mild to moderate adverse effects. Further, the results of this exploratory trial indicate that orismilast may lead to clinical improvements in HS. However, larger trials with tolerable dose ranges are warranted. The Trial is registered at Clinicaltrials.gov (UNI50007201) and EudraCT.ema.europa.eu (2021-000049-42).

Efficacy and safety of crisaborole ointment in Chinese and Japanese patients aged ≥2 years with mild-to-moderate atopic dermatitis.

Atopic dermatitis is a chronic inflammatory skin disease with a significant impact on the overall wellbeing of patients and their families. Crisaborole ointment, 2%, is a nonsteroidal phosphodiesterase 4 inhibitor approved for the treatment of mild-to-moderate atopic dermatitis in multiple countries. However, in the key pivotal trials, a low proportion of the overall patient population was Asian, therefore the safety and efficacy of crisaborole in the Asian population with atopic dermatitis remains unclear. CrisADe CLEAR was a multicenter, randomized, double-blind, vehicle-controlled, phase 3 study (NCT04360187) to assess the efficacy and safety of crisaborole ointment in Chinese and Japanese patients aged ≥2 years with mild-to-moderate atopic dermatitis involving ≥5% treatable body surface area. Patients were randomly assigned 2:1 to receive crisaborole or vehicle twice daily for 28 days. The primary endpoint was percentage change from baseline in the Eczema Area and Severity Index total score at day 29. Additional endpoints were improvement and success per Investigator's Static Global Assessment score at day 29 and change from baseline on the Peak Pruritus Numerical Rating Scale at week 4. Safety was assessed using rates of treatment emergent adverse events, serious adverse events, and clinically significant changes in vital signs and clinical laboratory parameters. Crisaborole-treated patients showed a significantly greater reduction versus vehicle in percentage change from baseline in Eczema Area and Severity Index total score at day 29 (P = 0.0002). Response rates for achievement of Investigator's Static Global Assessment improvement and success at day 29 were significantly higher for patients treated with crisaborole versus vehicle (P = 0.0124 and P = 0.0078, respectively). Crisaborole-treated patients showed a significantly greater reduction versus vehicle in change from baseline on the Peak Pruritus Numerical Rating Scale at week 4 (P = 0.0009). No new safety signals were identified. Treatment with crisaborole was effective and well tolerated in Chinese and Japanese patients with mild-to-moderate atopic dermatitis.

Effect of Roflumilast Cream vs Vehicle Cream on Chronic Plaque Psoriasis: The DERMIS-1 and DERMIS-2 Randomized Clinical Trials.

Importance: Once-daily roflumilast cream, 0.3%, a potent phosphodiesterase 4 inhibitor, demonstrated efficacy and was well tolerated in a phase 2b trial of patients with psoriasis. Objective: To evaluate the efficacy of roflumilast cream, 0.3%, applied once daily for 8 weeks in 2 trials of patients with plaque psoriasis. Design, Setting, and Participants: Two phase 3, randomized, double-blind, controlled, multicenter trials (DERMIS-1 [trial 1; n = 439] and DERMIS-2 [trial 2; n = 442]) were conducted at 40 centers (trial 1) and 39 centers (trial 2) in the US and Canada between December 9, 2019, and November 16, 2020, and between December 9, 2019, and November 23, 2020, respectively. Patients aged 2 years or older with plaque psoriasis involving 2% to 20% of body surface area were enrolled. The dates of final follow-up were November 20, 2020, and November 23, 2020, for trial 1 and trial 2, respectively. Interventions: Patients were randomized 2:1 to receive roflumilast cream, 0.3% (trial 1: n = 286; trial 2: n = 290), or vehicle cream (trial 1: n = 153; trial 2: n = 152) once daily for 8 weeks. Main Outcomes and Measures: The primary efficacy end point was Investigator Global Assessment (IGA) success (clear or almost clear status plus ≥2-grade improvement from baseline [score range, 0-4]) at week 8, analyzed using a Cochran-Mantel-Haenszel test stratified by site, baseline IGA score, and intertriginous involvement. There were 9 secondary outcomes, including intertriginous IGA success, 75% reduction in Psoriasis Area and Severity Index (PASI) score, and Worst Itch Numeric Rating Scale score of 4 or higher at baseline achieving 4-point reduction (WI-NRS success) at week 8 (scale: 0 [no itch] to 10 [worst imaginable itch]; minimum clinically important difference, 4 points). Results: Among 881 participants (mean age, 47.5 years; 320 [36.3%] female), mean IGA scores in trial 1 were 2.9 [SD, 0.52] for roflumilast and 2.9 [SD, 0.45] for vehicle and in trial 2 were 2.9 [SD, 0.48] for roflumilast and 2.9 [SD, 0.47]) for vehicle. Statistically significantly greater percentages of roflumilast-treated patients than vehicle-treated patients had IGA success at week 8 (trial 1: 42.4% vs 6.1%; difference, 39.6% [95% CI, 32.3%-46.9%]; trial 2: 37.5% vs 6.9%; difference, 28.9% [95% CI, 20.8%-36.9%]; P < .001 for both). Of 9 secondary end points, statistically significant differences favoring roflumilast vs vehicle were observed for 8 in trial 1 and 9 in trial 2, including intertriginous IGA success (71.2% vs 13.8%; difference, 66.5% [95% CI, 47.1%-85.8%] and 68.1% vs 18.5%; difference, 51.6% [95% CI, 29.3%-73.8%]; P < .001 for both), 75% reduction in PASI score (41.6% vs 7.6%; difference, 36.1% [95% CI, 28.5%-43.8%] and 39.0% vs 5.3%; difference, 32.4% [95% CI, 24.9%-39.8%]; P < .001 for both), WI-NRS success (67.5% vs 26.8%; difference, 42.6% [95% CI, 31.3%-53.8%] and 69.4% vs 35.6%; difference, 30.2% [95% CI, 18.2%-42.2%]; P < .001 for both). The incidence of treatment-emergent adverse events was 25.2% with roflumilast vs 23.5% with vehicle in trial 1 and 25.9% with roflumilast vs 18.4% with vehicle in trial 2. The incidence of serious adverse events was 0.7% with roflumilast vs 0.7% with vehicle in trial 1 and 0% with roflumilast vs 0.7% with vehicle in trial 2. Conclusions and Relevance: Among patients with chronic plaque psoriasis, treatment with roflumilast cream, 0.3%, compared with vehicle cream resulted in better clinical status at 8 weeks. Further research is needed to assess efficacy compared with other active treatments and to assess longer-term efficacy and safety. Trial Registration: ClinicalTrials.gov Identifiers: NCT04211363, NCT04211389.

Role of Roflumilast Combined with ESHAP Chemotherapy in Relapsed/Refractory Patients with Diffuse Large B-Cell Lymphoma.

PURPOSE: There are unmet needs associated with the current treatment strategies for relapsed/refractory diffuse large B-cell lymphoma (DLBCL) due to the poor treatment outcomes of these strategies. Roflumilast, a selective phosphodiesterase-4 inhibitor used for treating chronic obstructive pulmonary disease, is effective against B-cell malignancy via phosphoinositide 3-kinase (PI3K)-activity suppression. We analyzed the effects of roflumilast combined with ESHAP (etoposide, cisplatin, methylprednisolone, and cytarabine) chemotherapy in experimental and clinical settings. MATERIALS AND METHODS: An in vitro study using lymphoma cell lines and a pilot study on relapsed/refractory DLBCL patients were conducted to investigate the effects and mechanism of the combination of roflumilast and chemotherapy. The complete response (CR), overall response rate (ORR), and 1-year progression-free survival (PFS) were analyzed. RESULTS: We found that roflumilast is efficient when combined with other chemotherapy drugs, especially cytarabine. Synergistic effects between these two drugs influence the translation of mammalian target of rapamycin and myeloid cell leukemia 1, resulting in apoptosis and inhibition of B-cell lymphoma proliferation. In clinical setting, the roflumilast group showed better rates of CR (46.2% vs. 34.6%), ORR (76.9% vs. 53.8%), and 1-year PFS (50.0% vs. 25.9%) compared with the control group, though not statistically significant. The roflumilast group showed a higher incidence of asthenia and gastrointestinal adverse events. However, grade 3 or 4 adverse events were similar in both groups. CONCLUSION: We found that roflumilast, when combined with ESHAP chemotherapy, for relapsed/refractory DLBCL was clinically active and well tolerated. This combined treatment was able to suppress PI3K activity, which is correlated with the degree of clinical response.

Inhaled Phosphodiesterase Inhibitors for the Treatment of Chronic Obstructive Pulmonary Disease.

Phosphodiesterase (PDE) 4 inhibitors prevent the metabolism of cyclic adenosine monophosphate, thereby reducing inflammation. Inhaled PDE4 inhibitors aim to restrict systemic drug exposure to enhance the potential for clinical benefits (in the lungs) versus adverse events (systemically). The orally administered PDE4 inhibitor roflumilast reduces exacerbation rates in the subgroup of chronic obstructive pulmonary disease patients with a history of exacerbations and the presence of chronic bronchitis, but can cause PDE4 related adverse effects due to systemic exposure. CHF6001 is an inhaled PDE4 inhibitor, while inhaled ensifentrine is an inhibitor of both PDE3 and PDE4; antagonism of PDE3 facilitates smooth muscle relaxation and hence bronchodilation. These inhaled PDE inhibitors have both reported positive findings from early phase clinical trials, and have been well tolerated. Longer term trials are needed to firmly establish the clinical benefits of these drugs.

Pharmacokinetics and tolerability of apremilast in healthy Korean adult men.

We performed a two-part study to evaluate the pharmacokinetics, safety, and tolerability of oral apremilast, a phosphodiesterase 4 inhibitor indicated for the treatment of psoriasis, in healthy Korean adult men. In part 1, there were 12 subjects who randomly received a single oral dose of apremilast at 20, 30, or 40 mg in each of 3 periods in a crossover fashion. In part 2, there were 16 subjects who randomly received 30 mg of apremilast or its matching placebo in a ratio of 3:1 twice daily for 14 days. Apremilast was rapidly absorbed (maximum concentration: ~2-3 h postdose), and eliminated according to a monoexponential pattern with a terminal-phase elimination half-life of 8-9 h. The exposure to apremilast increased in a dose-proportional manner and accumulation was 1.6-fold at steady-state. Apremilast was well-tolerated after a single oral administration and multiple oral administrations in Korean adult men; all of the treatment-emergent adverse events were mild and recovered without sequelae. In conclusion, apremilast was safe and well-tolerated in healthy Korean adult men when administered single oral doses of 20, 30, or 40 mg or when administered multiple oral doses of 30 mg b.i.d. for 14 days. Overall exposures increased in an approximate dose proportional manner in healthy Korean adult men.

Preliminary evidence for the phosphodiesterase type-4 inhibitor, roflumilast, in ameliorating cognitive flexibility deficits in patients with schizophrenia.

BACKGROUND: Cognitive flexibility deficits are present in patients with schizophrenia and are strong predictors of functional outcome but, as yet, have no pharmacological treatments. AIMS: The purpose of this study was to investigate whether the phosphodiesterase type-4 inhibitor, roflumilast, can improve cognitive flexibility performance and functional brain activity in patients with schizophrenia. METHODS: This was a within-subject, randomised, double-blind, placebo-controlled, three-period crossover study using a version of the Intradimensional/Extradimensional (ID/ED) task, optimised for functional magnetic resonance imaging (fMRI), in 10 patients with schizophrenia who were scanned after receiving placebo, 100 µg or 250 µg roflumilast for 8 consecutive days. Data from an additional fMRI ID/ED study of 18 healthy participants on placebo was included to contextualise the schizophrenia-related performance and activations. The fMRI analyses included a priori driven region of interest (ROI) analysis of the dorsal frontoparietal attention network. RESULTS: Patients on placebo demonstrated broad deficits in task performance compared to the healthy comparison group, accompanied by preserved network activity for solution search, but reduced activity in left ventrolateral prefrontal cortex (VLPFC) and posterior parietal cortex for attentional set-shifting and reduced activity in left dorsolateral prefrontal cortex (DLPFC) for reversal learning. These ROI deficits were ameliorated by 250 µg roflumilast, whereas during solution search 100 µg roflumilast reduced activity in the left orbitofrontal cortex, right DLPFC and bilateral PPC, which was associated with an improvement in formation of attentional sets. CONCLUSIONS: The results suggest roflumilast has dose-dependent cognitive enhancing effects on the ID/ED task in patients with schizophrenia, and provides sufficient support for larger studies to test roflumilast's role in improving cognitive flexibility deficits in this clinical population.

The anti-depressant effects of a novel PDE4 inhibitor derived from resveratrol.

CONTEXT: Resveratrol has shown anti-stress and anti-depressant-like abilities involved in inhibiting phosphodiesterase-4 (PDE4) enzyme. However, its application is limited due to its low efficacy, bioavailability and selectivity. OBJECTIVE: This study synthesized a new resveratrol derivative RES003 and evaluated its PDE4 inhibitory and anti-depressant-like activities in vitro and in vivo, respectively. MATERIALS AND METHODS: PDEs inhibitory activities were evaluated by radioactive tracer method. Anti-depressant-like activities of novel resveratrol analogue (RES003) at doses of 2.5, 5.0 and 10 mg/kg was investigated by sugar water consumption and forced swimming tests using male ICR mice under chronic unpredictable stress procedure for 10 days. A total of 84 mice were randomly distributed into seven groups (n = 12). Drugs and vehicle were administered (intra-gastric or intra-peritoneal) once a day from the first to the last day. The molecular mechanisms were identified by western blot. RESULTS: RES003 showed more potent PDE4 inhibitory activity (half maximal inhibitory concentration (IC50), 0.87 µM) and better selectivity than resveratrol (IC50, 18.8 µM). RES003 could significantly increase the consumption of sugar water (p < 0.01) and immobility time (p < 0.01) compared to vehicle-treated stressed groups at doses of 5 and 10 mg/kg. Furthermore, RES003 could significantly increase the levels of cyclic adenosine monophosphate response element binding protein phosphorylation (10 mg/kg, p < 0.05) and brain-derived neurotrophic factor (BDNF) expression (5 and 10 mg/kg, p < 0.05 and 0.01) in mouse brain. DISCUSSION AND CONCLUSIONS: RES003 could ameliorate chronic stress induced depression-like behaviours through inhibition of PDE4 and activation of cAMP-triggered phosphorylation of cAMP response element binding protein/BDNF signalling pathway. Consequently, RES003 is a promising lead compound for the treatment of depression.

Atopic dermatitis: new insight into the etiology, pathogenesis, diagnosis and novel treatment strategies.

Atopic dermatitis (AD) is the long-lasting chronic inflammatory skin condition associated with cutaneous hyper-reactivity and triggered by environmental factors. The attributes of AD include dry skin, pruritus, lichenification and frequent eczematous abrasions. This has a strong heritable aspect and typically occurs with asthma and allergic rhinitis. The complex pathological mechanism behind AD etiology is epidermal barrier destruction resulting in the lack of filaggrin protein that can induce inflammation and T-cell infiltration. T-helper 2 cell-mediated pathways also bear the responsibility of damage to the epidermal barrier. Certain causative factors for AD include microbial imbalance of skin microbiota, immunoglobulin-E-induced sensitization and neuro-inflammation. Numerous beneficial topical and oral treatments have been available to patients and there are even more drugs in the pipeline for the treatment of AD. Topical moisturizers, corticosteroids, anti-inflammatory agents such as calcineurin inhibitors, phototherapy, cAMP-specific 3, 5 half-cyclic phosphodiesterase 4 inhibitors and systemic immunosuppressants are widely available for AD treatments. Different positions and pathways inside the immune system including JAK-STAT, phosphodiesterase 4, aryl hydrocarbon receptor and T-helper 2 cytokines are targeted by above-mentioned drug treatments. Instead of the severe side effects of topical steroids and oral antihistamines, herbal plants and their derived phytoconstituents are commonly used for the treatment of AD. A clear understanding of AD's cellular and molecular pathogenesis through substantial advancement in genetics, skin immunology and psychological factors resulted in advancement of AD management. Therefore, the review highlights the recent advancements in the understanding of clinical features, etiology, pathogenesis, treatment and management and non-adherence to AD treatment.

Monovalent antibody-conjugated lipid-polymer nanohybrids for active targeting to desmoglein 3 of keratinocytes to attenuate psoriasiform inflammation.

To improve the treatment of psoriasiform inflammation, we developed actively targeted nanocarriers loaded with the phosphodiesterase 4 inhibitor AN2728. Methods: Phospholipid-poly(lactic-co-glycolic acid) nanohybrids were prepared and conjugated with monovalent anti-desmoglein 3 antibody to bind keratinocytes. Results: The actively targeted nanohybrids were 229 nm in mean size with a nearly neutral surface charge. Flow cytometry and confocal microscopy showed a 9-fold increase in keratinocyte uptake of targeted nanohybrids relative to non-targeted nanoparticles. The nanoparticles localized mainly in lysosomes after internalization. AN2728-loaded antibody-conjugated nanocarriers inhibited cytokine/chemokine overexpression in activated keratinocytes without affecting cell viability. The targeted nanohybrids also suppressed neutrophil migration by reducing CXCL1 and CXCL2 release from keratinocytes. Following subcutaneous administration in mice, the nanohybrids distributed to the epidermis and hair follicles. In a psoriasis-like skin mouse model, the actively targeted nanoparticles were superior to free drug and non-targeted nanoparticles in mitigating skin inflammation. Intervention with the targeted nanosystem reduced the epidermal thickness of the psoriasiform lesion from 191 to 42 µm, decreased the Psoriasis Area Severity Index by 74%, restored barrier function, and returned chemokine levels to baseline. Conclusions: Our developed nanosystem was safe and demonstrated efficient targeting properties for the treatment of cutaneous inflammation.

Therapeutic potential of phosphodiesterase inhibitors in the treatment of osteoporosis: Scopes for therapeutic repurposing and discovery of new oral osteoanabolic drugs.

Cyclic nucleotide phosphodiesterases (PDEs) are ubiquitously expressed enzymes that hydrolyze phosphodiester bond in the second messenger molecules including cAMP and cGMP. A wide range of drugs blocks one or more PDEs thereby preventing the inactivation of cAMP/cGMP. PDEs are differentially expressed in bone cells including osteoblasts, osteoclasts and chondrocytes. Intracellular increases in cAMP/cGMP levels in osteoblasts result in osteogenic response. Acting via the type 1 PTH receptor, teriparatide and abaloparatide increase intracellular cAMP and induce osteoanabolic effect, and many PDE inhibitors mimic this effect in preclinical studies. Since all osteoanabolic drugs are injectable and that oral drugs are considered to improve the treatment adherence and persistence, osteogenic PDE inhibitors could be a promising alternative to the currently available osteogenic therapies and directly assessed clinically in drug repurposing mode. Similar to teriparatide/abaloparatide, PDE inhibitors while stimulating osteoblast function also promote osteoclast function through stimulation of receptor activator of nuclear factor kappa-B ligand production from osteoblasts. In this review, we critically discussed the effects of PDE inhibitors in bone cells from cellular signalling to a variety of preclinical models that evaluated the bone formation mechanisms. We identified pentoxifylline (a non-selective PDE inhibitor) and rolipram (a PDE4 selective inhibitor) being the most studied inhibitors with osteogenic effect in preclinical models of bone loss at ≤ human equivalent doses, which suggest their potential for post-menopausal osteoporosis treatment through therapeutic repurposing. Subsequently, we treated pentoxifylline and rolipram as prototypical osteogenic PDEs to predict new chemotypes via the computer-aided design strategies for new drugs, based on the structural biology of PDEs.

Adjunctive host-directed therapies for pulmonary tuberculosis: a prospective, open-label, phase 2, randomised controlled trial.

BACKGROUND: Current tuberculosis treatments leave patients with clinically significant lung injury and increased all-cause mortality post-cure. Adjunctive host-directed therapies could protect the lungs, improve long-term survival, and shorten treatment duration; however, few have been tested clinically. Therefore, we aimed to assess the safety and preliminary efficacy of four host-directed therapies for tuberculosis. METHODS: In this prospective, open-label, phase 2, randomised controlled trial, patients with pulmonary tuberculosis were recruited at three clinical sites in South Africa. Eligible patients were aged 18-65 years, HIV-1-negative, and had rifampicin-susceptible Mycobacterium tuberculosis, a sputum Xpert cycle threshold of less than 20, and moderately advanced or far advanced disease on chest radiography. By use of numbers generated in blocks of ten and stratification by site, eligible patients were randomly assigned (1:1:1:1:1) to receive one of the four oral host-directed treatments plus standard tuberculosis treatment or standard treatment alone (the control group). Host-directed treatments were: CC-11050 (200 mg twice daily, taken with food; day 1-112); everolimus (0·5 mg/day; day 1-112); auranofin (3 mg/day for seven doses, then 6 mg/day; day 1-112); and ergocalciferol (5 mg on day 1, then 2·5 mg on day 28 and day 56). All study participants received oral rifabutin-substituted standard tuberculosis treatment for 180 days. Patients and clinicians were not masked to treatment assignment. Spirometry and sputum culture with solid and liquid media were done at baseline and up to 180 days at specified intervals throughout treatment. The primary endpoint was safety and tolerability up to day 210. Secondary preliminary efficacy endpoints were treatment effects on sputum microbiology (culture status at day 56 and the hazard ratio for stable culture conversion up to day 180) and lung function (FEV1 and forced vital capacity [FVC]) measured by spirometry at day 56, day 180, and day 540. Safety was analysed in the intention-to-treat population and preliminary efficacy primarily in the per-protocol population. The trial is registered at ClinicalTrials.gov, NCT02968927. Post-treatment follow-up was completed in 2020. FINDINGS: Between Nov 18, 2016, and Sept 27, 2018, 200 patients were screened and randomly assigned to different treatment groups (n=40 per group, apart from n=39 in the everolimus group after one patient withdrew consent). 11 treatment-emergent serious adverse events occurred either during treatment or within 30 days after treatment discontinuation, of which three were attributable to a host-directed treatment. Life-threatening thrombocytopenia occurred in an auranofin recipient; apparent intra-abdominal sepsis leading to death occurred in another auranofin recipient and was classified as a suspected unexpected serious adverse reaction. Tuberculous spondylitis occurred as an apparent paradoxical reaction in a patient receiving ergocalciferol. Two patients in the control group had life-threatening, treatment-attributable liver injury. No treatment-emergent, treatment-attributable serious adverse events occurred in patients receiving CC-11050 or everolimus. Mean FEV1 in the control group was 61·7% of predicted (95% CI 56·3-67·1) at baseline and 69·1% (62·3-75·8) at day 180. Patients treated with CC-11050 and everolimus had increased recovery of FEV1 at day 180 relative to the control group (mean difference from control group 6·30%, 95% CI 0·06-12·54; p=0·048; and 6·56%, 0·18-12·95; p=0·044, respectively), whereas auranofin and ergocalciferol recipients did not. None of the treatments had an effect on FVC during 180 days of follow-up or on measures of sputum culture status over the course of the study. INTERPRETATION: CC-11050 and everolimus were safe and reasonably well tolerated as adjunctive therapies for tuberculosis, and analysis of preliminary efficacy suggests they might also enhance the recovery of FEV1, a key measure of lung function and predictor of all-cause mortality. Further studies of these candidates are warranted. FUNDING: The Bill & Melinda Gates Foundation and the South African Medical Research Council.

Inhibition of cAMP-phosphodiesterase 4 (PDE4) potentiates the anesthetic effects of Isoflurane in mice.

Despite major advances, there remains a need for novel anesthetic drugs or drug combinations with improved efficacy and safety profiles. Here, we show that inhibition of cAMP-phosphodiesterase 4 (PDE4), while not inducing anesthesia by itself, potently enhances the anesthetic effects of Isoflurane in mice. Treatment with several distinct PAN-PDE4 inhibitors, including Rolipram, Piclamilast, Roflumilast, and RS25344, significantly delayed the time-to-righting after Isoflurane anesthesia. Conversely, treatment with a PDE3 inhibitor, Cilostamide, or treatment with the potent, but non-brain-penetrant PDE4 inhibitor YM976, had no effect. These findings suggest that potentiation of Isoflurane hypnosis is a class effect of brain-penetrant PDE4 inhibitors, and that they act by synergizing with Isoflurane in inhibiting neuronal activity. The PDE4 family comprises four PDE4 subtypes, PDE4A to PDE4D. Genetic deletion of any of the four PDE4 subtypes in mice did not affect Isoflurane anesthesia per se. However, PDE4D knockout mice are largely protected from the effect of pharmacologic PDE4 inhibition, suggesting that PDE4D is the predominant, but not the sole PDE4 subtype involved in potentiating Isoflurane anesthesia. Pretreatment with Naloxone or Propranolol alleviated the potentiating effect of PDE4 inhibition, implicating opioid- and ß-adrenoceptor signaling in mediating PDE4 inhibitor-induced augmentation of Isoflurane anesthesia. Conversely, stimulation or blockade of α1-adrenergic, α2-adrenergic or serotonergic signaling did not affect the potentiation of Isoflurane hypnosis by PDE4 inhibition. We further show that pretreatment with a PDE4 inhibitor boosts the delivery of bacteria into the lungs of mice after intranasal infection under Isoflurane, thus providing a first example that PDE4 inhibitor-induced potentiation of Isoflurane anesthesia can critically impact animal models and must be considered as a factor in experimental design. Our findings suggest that PDE4/PDE4D inhibition may serve as a tool to delineate the exact molecular mechanisms of Isoflurane anesthesia, which remain poorly understood, and may potentially be exploited to reduce the clinical doses of Isoflurane required to maintain hypnosis.

The effects of roflumilast, a phosphodiesterase type-4 inhibitor, on EEG biomarkers in schizophrenia: A randomised controlled trial.

BACKGROUND: Patients with schizophrenia have significant cognitive deficits, which may profoundly impair quality of life. These deficits are also evident at the neurophysiological level with patients demonstrating altered event-related potential in several stages of cognitive processing compared to healthy controls; within the auditory domain, for example, there are replicated alterations in Mismatch Negativity, P300 and Auditory Steady State Response. However, there are no approved pharmacological treatments for cognitive deficits in schizophrenia. AIMS: Here we examine whether the phosphodiesterase-4 inhibitor, roflumilast, can improve neurophysiological deficits in schizophrenia. METHODS: Using a randomised, double-blind, placebo-controlled, crossover design study in 18 patients with schizophrenia, the effect of the phosphodiesterase-4 inhibitor, roflumilast (100 µg and 250 µg) on auditory steady state response (early stage), mismatch negativity and theta (intermediate stage) and P300 (late stage) was examined using electroencephalogram. A total of 18 subjects were randomised and included in the analysis. RESULTS: Roflumilast 250 µg significantly enhanced the amplitude of both the mismatch negativity (p=0.04) and working memory-related theta oscillations (p=0.02) compared to placebo but not in the other (early- or late-stage) cognitive markers. CONCLUSIONS: The results suggest that phosphodiesterase-4 inhibition, with roflumilast, can improve electroencephalogram cognitive markers, which are impaired in schizophrenia, and that phosphodiesterase-4 inhibition acts at an intermediate rather than early or late cognitive processing stage. This study also underlines the use of neurophysiological measures as cognitive biomarkers in experimental medicine.