Low-Dose Methotrexate Pharmacokinetics and Pharmacodynamics in the Therapy of Severe Psoriasis

Systemic pharmacological treatments for chronic plaque psoriasis: a network meta-analysis

BACKGROUND

Psoriasis is an immune-mediated disease with either skin or joints manifestations, or both, and it has a major impact on quality of life. Although there is currently no cure for psoriasis, various treatment strategies allow sustained control of disease signs and symptoms. The relative benefit of these treatments remains unclear due to the limited number of trials comparing them directly head-to-head, which is why we chose to conduct a network meta-analysis.

OBJECTIVES

To compare the benefits and harms of non-biological systemic agents, small molecules, and biologics for people with moderate-to-severe psoriasis using a network meta-analysis, and to provide a ranking of these treatments according to their benefits and harms.

SEARCH METHODS

For this update of the living systematic review, we updated our searches of the following databases monthly to October 2022: the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, and Embase.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of systemic treatments in adults over 18 years with moderate-to-severe plaque psoriasis, at any stage of treatment, compared to placebo or another active agent. The primary outcomes were: proportion of participants who achieved clear or almost clear skin, that is, at least Psoriasis Area and Severity Index (PASI) 90; proportion of participants with serious adverse events (SAEs) at induction phase (8 to 24 weeks after randomisation).

DATA COLLECTION AND ANALYSIS

We conducted duplicate study selection, data extraction, risk of bias assessment, and analyses. We synthesised data using pairwise and network meta-analysis (NMA) to compare treatments and rank them according to effectiveness (PASI 90 score) and acceptability (inverse of SAEs). We assessed the certainty of NMA evidence for the two primary outcomes and all comparisons using CINeMA, as very low, low, moderate, or high. We contacted study authors when data were unclear or missing. We used the surface under the cumulative ranking curve (SUCRA) to infer treatment hierarchy, from 0% (worst for effectiveness or safety) to 100% (best for effectiveness or safety).

MAIN RESULTS

This update includes an additional 12 studies, taking the total number of included studies to 179, and randomised participants to 62,339, 67.1% men, mainly recruited from hospitals. Average age was 44.6 years, mean PASI score at baseline was 20.4 (range: 9.5 to 39). Most studies were placebo-controlled (56%). We assessed a total of 20 treatments. Most (152) trials were multicentric (two to 231 centres). One-third of the studies (65/179) had high risk of bias, 24 unclear risk, and most (90) low risk. Most studies (138/179) declared funding by a pharmaceutical company, and 24 studies did not report a funding source. Network meta-analysis at class level showed that all interventions (non-biological systemic agents, small molecules, and biological treatments) showed a higher proportion of patients reaching PASI 90 than placebo. Anti-IL17 treatment showed a higher proportion of patients reaching PASI 90 compared to all the interventions. Biologic treatments anti-IL17, anti-IL12/23, anti-IL23, and anti-TNF alpha showed a higher proportion of patients reaching PASI 90 than the non-biological systemic agents. For reaching PASI 90, the most effective drugs when compared to placebo were (SUCRA rank order, all high-certainty evidence): infliximab (risk ratio (RR) 49.16, 95% CI 20.49 to 117.95), bimekizumab (RR 27.86, 95% CI 23.56 to 32.94), ixekizumab (RR 27.35, 95% CI 23.15 to 32.29), risankizumab (RR 26.16, 95% CI 22.03 to 31.07). Clinical effectiveness of these drugs was similar when compared against each other. Bimekizumab and ixekizumab were significantly more likely to reach PASI 90 than secukinumab. Bimekizumab, ixekizumab, and risankizumab were significantly more likely to reach PASI 90 than brodalumab and guselkumab. Infliximab, anti-IL17 drugs (bimekizumab, ixekizumab, secukinumab, and brodalumab), and anti-IL23 drugs except tildrakizumab were significantly more likely to reach PASI 90 than ustekinumab, three anti-TNF alpha agents, and deucravacitinib. Ustekinumab was superior to certolizumab. Adalimumab, tildrakizumab, and ustekinumab were superior to etanercept. No significant difference was shown between apremilast and two non-biological drugs: ciclosporin and methotrexate. We found no significant difference between any of the interventions and the placebo for the risk of SAEs. The risk of SAEs was significantly lower for participants on methotrexate compared with most of the interventions. Nevertheless, the SAE analyses were based on a very low number of events with very low- to moderate-certainty evidence for all the comparisons. The findings therefore have to be viewed with caution. For other efficacy outcomes (PASI 75 and Physician Global Assessment (PGA) 0/1), the results were similar to the results for PASI 90. Information on quality of life was often poorly reported and was absent for several of the interventions.

AUTHORS' CONCLUSIONS

Our review shows that, compared to placebo, the biologics infliximab, bimekizumab, ixekizumab, and risankizumab were the most effective treatments for achieving PASI 90 in people with moderate-to-severe psoriasis on the basis of high-certainty evidence. This NMA evidence is limited to induction therapy (outcomes measured from 8 to 24 weeks after randomisation), and is not sufficient for evaluating longer-term outcomes in this chronic disease. Moreover, we found low numbers of studies for some of the interventions, and the young age (mean 44.6 years) and high level of disease severity (PASI 20.4 at baseline) may not be typical of patients seen in daily clinical practice. We found no significant difference in the assessed interventions and placebo in terms of SAEs, and the safety evidence for most interventions was very low to moderate quality. More randomised trials directly comparing active agents are needed, and these should include systematic subgroup analyses (sex, age, ethnicity, comorbidities, psoriatic arthritis). To provide long-term information on the safety of treatments included in this review, an evaluation of non-randomised studies is needed. Editorial note: This is a living systematic review. Living systematic reviews offer a new approach to review updating, in which the review is continually updated, incorporating relevant new evidence as it becomes available. Please refer to the Cochrane Database of Systematic Reviews for the current status of this review.

Methotrexate Dosing Regimen for Plaque-type Psoriasis: An Update of a Systematic Review

Background Methotrexate (MTX) is a systemic treatment for plaque-type psoriasis. At the time of approval, no dose-ranging studies were performed. Nowadays, a uniform dosing regimen is lacking. This might contribute to suboptimal treatment with the drug.Objective To summarize the literature involving the MTX dosing regimens in psoriasis patients.Methods In this SR, RCTs and documents with aggregated evidence (AgEv) on the MTX dosing regimen in psoriasis were summarized. All randomized controlled trials (RCTs) in which oral, subcutaneous or intramuscular MTX was used in patients with psoriasis and AgEv, were included. The MEDLINE, EMBASE and CENTRAL databases were searched up to June 20, 2022. This SR was registered in PROSPERO.Results Thirty-nine RCTs had a high risk of bias. Test dosages were given in only 3 RCTs. In the RCTs, MTX was usually prescribed in a start dose of 7.5 mg/week (n = 13). MTX was mostly given in a start dose of 15 mg/week, in the AgEv (n = 5). One guideline recommended a test dose, in other aggregated evidence a test dose was not mentioned or even discouraged.Conclusions There is a lack of high-quality evidence and available data for dosing MTX in psoriasis is heterogeneous.

Systemic pharmacological treatments for chronic plaque psoriasis: a network meta-analysis

BACKGROUND

Psoriasis is an immune-mediated disease with either skin or joints manifestations, or both, and it has a major impact on quality of life. Although there is currently no cure for psoriasis, various treatment strategies allow sustained control of disease signs and symptoms. The relative benefit of these treatments remains unclear due to the limited number of trials comparing them directly head-to-head, which is why we chose to conduct a network meta-analysis.

OBJECTIVES

To compare the efficacy and safety of non-biological systemic agents, small molecules, and biologics for people with moderate-to-severe psoriasis using a network meta-analysis, and to provide a ranking of these treatments according to their efficacy and safety.

SEARCH METHODS

For this update of the living systematic review, we updated our searches of the following databases monthly to October 2021: the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, and Embase.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of systemic treatments in adults over 18 years with moderate-to-severe plaque psoriasis, at any stage of treatment, compared to placebo or another active agent. The primary outcomes were: proportion of participants who achieved clear or almost clear skin, that is, at least Psoriasis Area and Severity Index (PASI) 90; proportion of participants with serious adverse events (SAEs) at induction phase (8 to 24 weeks after randomisation).

DATA COLLECTION AND ANALYSIS

We conducted duplicate study selection, data extraction, risk of bias assessment and analyses. We synthesised data using pairwise and network meta-analysis (NMA) to compare treatments and rank them according to effectiveness (PASI 90 score) and acceptability (inverse of SAEs). We assessed the certainty of NMA evidence for the two primary outcomes and all comparisons using CINeMA, as very low, low, moderate, or high. We contacted study authors when data were unclear or missing. We used the surface under the cumulative ranking curve (SUCRA) to infer treatment hierarchy, from 0% (worst for effectiveness or safety) to 100% (best for effectiveness or safety).

MAIN RESULTS

This update includes an additional 19 studies, taking the total number of included studies to 167, and randomised participants to 58,912, 67.2% men, mainly recruited from hospitals. Average age was 44.5 years, mean PASI score at baseline was 20.4 (range: 9.5 to 39). Most studies were placebo-controlled (57%). We assessed a total of 20 treatments. Most (140) trials were multicentric (two to 231 centres). One-third of the studies (57/167) had high risk of bias; 23 unclear risk, and most (87) low risk. Most studies (127/167) declared funding by a pharmaceutical company, and 24 studies did not report a funding source. Network meta-analysis at class level showed that all interventions (non-biological systemic agents, small molecules, and biological treatments) showed a higher proportion of patients reaching PASI 90 than placebo. Anti-IL17 treatment showed a higher proportion of patients reaching PASI 90 compared to all the interventions, except anti-IL23. Biologic treatments anti-IL17, anti-IL12/23, anti-IL23 and anti-TNF alpha showed a higher proportion of patients reaching PASI 90 than the non-biological systemic agents. For reaching PASI 90, the most effective drugs when compared to placebo were (SUCRA rank order, all high-certainty evidence): infliximab (risk ratio (RR) 50.19, 95% CI 20.92 to 120.45), bimekizumab (RR 30.27, 95% CI 25.45 to 36.01), ixekizumab (RR 30.19, 95% CI 25.38 to 35.93), risankizumab (RR 28.75, 95% CI 24.03 to 34.39). Clinical effectiveness of these drugs was similar when compared against each other. Bimekizumab, ixekizumab and risankizumab showed a higher proportion of patients reaching PASI 90 than other anti-IL17 drugs (secukinumab and brodalumab) and guselkumab. Infliximab, anti-IL17 drugs (bimekizumab, ixekizumab, secukinumab and brodalumab) and anti-IL23 drugs (risankizumab and guselkumab) except tildrakizumab showed a higher proportion of patients reaching PASI 90 than ustekinumab and three anti-TNF alpha agents (adalimumab, certolizumab and etanercept). Ustekinumab was superior to certolizumab; adalimumab and ustekinumab were superior to etanercept. No significant difference was shown between apremilast and two non-biological drugs: ciclosporin and methotrexate. We found no significant difference between any of the interventions and the placebo for the risk of SAEs. The risk of SAEs was significantly lower for participants on methotrexate compared with most of the interventions. Nevertheless, the SAE analyses were based on a very low number of events with low- to moderate-certainty for all the comparisons (except methotrexate versus placebo, which was high-certainty). The findings therefore have to be viewed with caution. For other efficacy outcomes (PASI 75 and Physician Global Assessment (PGA) 0/1), the results were similar to the results for PASI 90. Information on quality of life was often poorly reported and was absent for several of the interventions.

AUTHORS' CONCLUSIONS

Our review shows that, compared to placebo, the biologics infliximab, bimekizumab, ixekizumab, and risankizumab were the most effective treatments for achieving PASI 90 in people with moderate-to-severe psoriasis on the basis of high-certainty evidence. This NMA evidence is limited to induction therapy (outcomes measured from 8 to 24 weeks after randomisation), and is not sufficient for evaluating longer-term outcomes in this chronic disease. Moreover, we found low numbers of studies for some of the interventions, and the young age (mean 44.5 years) and high level of disease severity (PASI 20.4 at baseline) may not be typical of patients seen in daily clinical practice. We found no significant difference in the assessed interventions and placebo in terms of SAEs, and the safety evidence for most interventions was low to moderate quality. More randomised trials directly comparing active agents are needed, and these should include systematic subgroup analyses (sex, age, ethnicity, comorbidities, psoriatic arthritis). To provide long-term information on the safety of treatments included in this review, an evaluation of non-randomised studies and postmarketing reports from regulatory agencies is needed. Editorial note: This is a living systematic review. Living systematic reviews offer a new approach to review updating, in which the review is continually updated, incorporating relevant new evidence as it becomes available. Please refer to the Cochrane Database of Systematic Reviews for the current status of this review.

Comparison of the clinical efficacy of subcutaneous versus oral administration of methotrexate in patients with psoriasis vulgaris: a randomized controlled trial

BACKGROUND

Evidence demonstrates that parenteral administration of methotrexate (MTX) has a higher drug bioavailability with respect to the oral route of administration. This difference is even more pronounced for medium-to-high dosages.

OBJECTIVES

To compare the efficacy, safety, and tolerability of oral and subcutaneous (SC) MTX for treatment of psoriasis.

METHODS

A randomized, comparative, single-blind, 32-week study was conducted. The clinical response was evaluated using the Psoriasis Area Severity Index (PASI) and the patient global assessment was assessed using the Visual Analog Scale (VAS).

RESULTS

Seventy-seven patients had completed the study, 38 in SC and 39 in oral MTX group. No significant between-group differences were found in PASI 75 (p=0.14, 0.21), PASI 90 (p=0.23, 0.18), and PASI 100 (p=0.62, 0.22) responses at week 16 and 32, respectively. The mean VAS, however, throughout the 32-week study according to the multivariable analysis showed that SC MTX was superior to oral MTX for patient evaluation of disease improvement. Adverse events were comparable in both groups.

CONCLUSIONS

Subcutaneous and oral administration of MTX had similar efficacies in improving the PASI score even at the highest tolerable dose. The SC MTX group, however, had higher overall patient satisfaction than the oral MTX group. No difference in tolerability was found.

Systemic pharmacological treatments for chronic plaque psoriasis: a network meta-analysis

BACKGROUND

Psoriasis is an immune-mediated disease for which some people have a genetic predisposition. The condition manifests in inflammatory effects on either the skin or joints, or both, and it has a major impact on quality of life. Although there is currently no cure for psoriasis, various treatment strategies allow sustained control of disease signs and symptoms. Several randomised controlled trials (RCTs) have compared the efficacy of the different systemic treatments in psoriasis against placebo. However, the relative benefit of these treatments remains unclear due to the limited number of trials comparing them directly head-to-head, which is why we chose to conduct a network meta-analysis.

OBJECTIVES

To compare the efficacy and safety of non-biological systemic agents, small molecules, and biologics for people with moderate-to-severe psoriasis using a network meta-analysis, and to provide a ranking of these treatments according to their efficacy and safety.

SEARCH METHODS

For this living systematic review we updated our searches of the following databases monthly to September 2020: the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, and Embase. We searched two trials registers to the same date. We checked the reference lists of included studies and relevant systematic reviews for further references to eligible RCTs.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of systemic treatments in adults (over 18 years of age) with moderate-to-severe plaque psoriasis or psoriatic arthritis whose skin had been clinically diagnosed with moderate-to-severe psoriasis, at any stage of treatment, in comparison to placebo or another active agent. The primary outcomes of this review were: the proportion of participants who achieved clear or almost clear skin, that is, at least Psoriasis Area and Severity Index (PASI) 90 at induction phase (from 8 to 24 weeks after the randomisation), and the proportion of participants with serious adverse events (SAEs) at induction phase. We did not evaluate differences in specific adverse events.

DATA COLLECTION AND ANALYSIS

Several groups of two review authors independently undertook study selection, data extraction, 'Risk of bias' assessment, and analyses. We synthesised the data using pair-wise and network meta-analysis (NMA) to compare the treatments of interest and rank them according to their effectiveness (as measured by the PASI 90 score) and acceptability (the inverse of serious adverse events). We assessed the certainty of the body of evidence from the NMA for the two primary outcomes and all comparisons, according to CINeMA, as either very low, low, moderate, or high. We contacted study authors when data were unclear or missing. We used the surface under the cumulative ranking curve (SUCRA) to infer on treatment hierarchy: 0% (treatment is the worst for effectiveness or safety) to 100% (treatment is the best for effectiveness or safety).

MAIN RESULTS

We included 158 studies (18 new studies for the update) in our review (57,831 randomised participants, 67.2% men, mainly recruited from hospitals). The overall average age was 45 years; the overall mean PASI score at baseline was 20 (range: 9.5 to 39). Most of these studies were placebo-controlled (58%), 30% were head-to-head studies, and 11% were multi-armed studies with both an active comparator and a placebo. We have assessed a total of 20 treatments. In all, 133 trials were multicentric (two to 231 centres). All but two of the outcomes included in this review were limited to the induction phase (assessment from 8 to 24 weeks after randomisation). We assessed many studies (53/158) as being at high risk of bias; 25 were at an unclear risk, and 80 at low risk. Most studies (123/158) declared funding by a pharmaceutical company, and 22 studies did not report their source of funding. Network meta-analysis at class level showed that all of the interventions (non-biological systemic agents, small molecules, and biological treatments) were significantly more effective than placebo in reaching PASI 90. At class level, in reaching PASI 90, the biologic treatments anti-IL17, anti-IL12/23, anti-IL23, and anti-TNF alpha were significantly more effective than the small molecules and the non-biological systemic agents. At drug level, infliximab, ixekizumab, secukinumab, brodalumab, risankizumab and guselkumab were significantly more effective in reaching PASI 90 than ustekinumab and three anti-TNF alpha agents: adalimumab, certolizumab, and etanercept. Ustekinumab and adalimumab were significantly more effective in reaching PASI 90 than etanercept; ustekinumab was more effective than certolizumab, and the clinical effectiveness of ustekinumab and adalimumab was similar. There was no significant difference between tofacitinib or apremilast and three non-biological drugs: fumaric acid esters (FAEs), ciclosporin and methotrexate. Network meta-analysis also showed that infliximab, ixekizumab, risankizumab, bimekizumab, secukinumab, guselkumab, and brodalumab outperformed other drugs when compared to placebo in reaching PASI 90. The clinical effectiveness of these drugs was similar, except for ixekizumab which had a better chance of reaching PASI 90 compared with secukinumab, guselkumab and brodalumab. The clinical effectiveness of these seven drugs was: infliximab (versus placebo): risk ratio (RR) 50.29, 95% confidence interval (CI) 20.96 to 120.67, SUCRA = 93.6; high-certainty evidence; ixekizumab (versus placebo): RR 32.48, 95% CI 27.13 to 38.87; SUCRA = 90.5; high-certainty evidence; risankizumab (versus placebo): RR 28.76, 95% CI 23.96 to 34.54; SUCRA = 84.6; high-certainty evidence; bimekizumab (versus placebo): RR 58.64, 95% CI 3.72 to 923.86; SUCRA = 81.4; high-certainty evidence; secukinumab (versus placebo): RR 25.79, 95% CI 21.61 to 30.78; SUCRA = 76.2; high-certainty evidence; guselkumab (versus placebo): RR 25.52, 95% CI 21.25 to 30.64; SUCRA = 75; high-certainty evidence; and brodalumab (versus placebo): RR 23.55, 95% CI 19.48 to 28.48; SUCRA = 68.4; moderate-certainty evidence. Conservative interpretation is warranted for the results for bimekizumab (as well as mirikizumab, tyrosine kinase 2 inhibitor, acitretin, ciclosporin, fumaric acid esters, and methotrexate), as these drugs, in the NMA, have been evaluated in few trials. We found no significant difference between any of the interventions and the placebo for the risk of SAEs. Nevertheless, the SAE analyses were based on a very low number of events with low to moderate certainty for all the comparisons. Thus, the results have to be viewed with caution and we cannot be sure of the ranking. For other efficacy outcomes (PASI 75 and Physician Global Assessment (PGA) 0/1) the results were similar to the results for PASI 90. Information on quality of life was often poorly reported and was absent for several of the interventions.

AUTHORS' CONCLUSIONS

Our review shows that compared to placebo, the biologics infliximab, ixekizumab, risankizumab, bimekizumab, secukinumab, guselkumab and brodalumab were the most effective treatments for achieving PASI 90 in people with moderate-to-severe psoriasis on the basis of moderate- to high-certainty evidence. This NMA evidence is limited to induction therapy (outcomes were measured from 8 to 24 weeks after randomisation) and is not sufficient for evaluation of longer-term outcomes in this chronic disease. Moreover, we found low numbers of studies for some of the interventions, and the young age (mean age of 45 years) and high level of disease severity (PASI 20 at baseline) may not be typical of patients seen in daily clinical practice. Another major concern is that short-term trials provide scanty and sometimes poorly-reported safety data and thus do not provide useful evidence to create a reliable risk profile of treatments. We found no significant difference in the assessed interventions and placebo in terms of SAEs, and the evidence for all the interventions was of low to moderate quality. In order to provide long-term information on the safety of the treatments included in this review, it will also be necessary to evaluate non-randomised studies and postmarketing reports released from regulatory agencies. In terms of future research, randomised trials directly comparing active agents are necessary once high-quality evidence of benefit against placebo is established, including head-to-head trials amongst and between non-biological systemic agents and small molecules, and between biological agents (anti-IL17 versus anti-IL23, anti-IL23 versus anti-IL12/23, anti-TNF alpha versus anti-IL12/23). Future trials should also undertake systematic subgroup analyses (e.g. assessing biological-naïve participants, baseline psoriasis severity, presence of psoriatic arthritis, etc.). Finally, outcome measure harmonisation is needed in psoriasis trials, and researchers should look at the medium- and long-term benefit and safety of the interventions and the comparative safety of different agents. Editorial note: This is a living systematic review. Living systematic reviews offer a new approach to review updating, in which the review is continually updated, incorporating relevant new evidence as it becomes available. Please refer to the Cochrane Database of Systematic Reviews for the current status of this review.

Systemic pharmacological treatments for chronic plaque psoriasis: a network meta-analysis

BACKGROUND

Psoriasis is an immune-mediated disease for which some people have a genetic predisposition. The condition manifests in inflammatory effects on either the skin or joints, or both, and it has a major impact on quality of life. Although there is currently no cure for psoriasis, various treatment strategies allow sustained control of disease signs and symptoms. Several randomised controlled trials (RCTs) have compared the efficacy of the different systemic treatments in psoriasis against placebo. However, the relative benefit of these treatments remains unclear due to the limited number of trials comparing them directly head-to-head, which is why we chose to conduct a network meta-analysis. This is the baseline update of a Cochrane Review first published in 2017, in preparation for this Cochrane Review becoming a living systematic review.

OBJECTIVES

To compare the efficacy and safety of conventional systemic agents, small molecules, and biologics for people with moderate-to-severe psoriasis, and to provide a ranking of these treatments according to their efficacy and safety.

SEARCH METHODS

We updated our research using the following databases to January 2019: the Cochrane Skin Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, LILACS and the conference proceedings of a number of dermatology meetings. We also searched five trials registers and the US Food and Drug Administration (FDA) and European Medicines Agency (EMA) reports (until June 2019). We checked the reference lists of included and excluded studies for further references to relevant RCTs.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of systemic treatments in adults (over 18 years of age) with moderate-to-severe plaque psoriasis or psoriatic arthritis whose skin had been clinically diagnosed with moderate-to-severe psoriasis, at any stage of treatment, in comparison to placebo or another active agent. The primary outcomes of this review were: the proportion of participants who achieved clear or almost clear skin, that is, at least Psoriasis Area and Severity Index (PASI) 90 at induction phase (from 8 to 24 weeks after the randomisation), and the proportion of participants with serious adverse effects (SAEs) at induction phase. We did not evaluate differences in specific adverse effects.

DATA COLLECTION AND ANALYSIS

Several groups of two review authors independently undertook study selection, data extraction, 'Risk of bias' assessment, and analyses. We synthesised the data using pair-wise and network meta-analysis (NMA) to compare the treatments of interest and rank them according to their effectiveness (as measured by the PASI 90 score) and acceptability (the inverse of serious adverse effects). We assessed the certainty of the body of evidence from the NMA for the two primary outcomes, according to GRADE, as either very low, low, moderate, or high. We contacted study authors when data were unclear or missing.

MAIN RESULTS

We included 140 studies (31 new studies for the update) in our review (51,749 randomised participants, 68% men, mainly recruited from hospitals). The overall average age was 45 years; the overall mean PASI score at baseline was 20 (range: 9.5 to 39). Most of these studies were placebo-controlled (59%), 30% were head-to-head studies, and 11% were multi-armed studies with both an active comparator and a placebo. We have assessed a total of 19 treatments. In all, 117 trials were multicentric (two to 231 centres). All but two of the outcomes included in this review were limited to the induction phase (assessment from 8 to 24 weeks after randomisation). We assessed many studies (57/140) as being at high risk of bias; 42 were at an unclear risk, and 41 at low risk. Most studies (107/140) declared funding by a pharmaceutical company, and 22 studies did not report the source of funding. Network meta-analysis at class level showed that all of the interventions (conventional systemic agents, small molecules, and biological treatments) were significantly more effective than placebo in terms of reaching PASI 90. At class level, in terms of reaching PASI 90, the biologic treatments anti-IL17, anti-IL12/23, anti-IL23, and anti-TNF alpha were significantly more effective than the small molecules and the conventional systemic agents. At drug level, in terms of reaching PASI 90, infliximab, all of the anti-IL17 drugs (ixekizumab, secukinumab, bimekizumab and brodalumab) and the anti-IL23 drugs (risankizumab and guselkumab, but not tildrakizumab) were significantly more effective in reaching PASI 90 than ustekinumab and 3 anti-TNF alpha agents: adalimumab, certolizumab and etanercept. Adalimumab and ustekinumab were significantly more effective in reaching PASI 90 than certolizumab and etanercept. There was no significant difference between tofacitinib or apremilast and between two conventional drugs: ciclosporin and methotrexate. Network meta-analysis also showed that infliximab, ixekizumab, risankizumab, bimekizumab, guselkumab, secukinumab and brodalumab outperformed other drugs when compared to placebo in reaching PASI 90. The clinical effectiveness for these seven drugs was similar: infliximab (versus placebo): risk ratio (RR) 29.52, 95% confidence interval (CI) 19.94 to 43.70, Surface Under the Cumulative Ranking (SUCRA) = 88.5; moderate-certainty evidence; ixekizumab (versus placebo): RR 28.12, 95% CI 23.17 to 34.12, SUCRA = 88.3, moderate-certainty evidence; risankizumab (versus placebo): RR 27.67, 95% CI 22.86 to 33.49, SUCRA = 87.5, high-certainty evidence; bimekizumab (versus placebo): RR 58.64, 95% CI 3.72 to 923.86, SUCRA = 83.5, low-certainty evidence; guselkumab (versus placebo): RR 25.84, 95% CI 20.90 to 31.95; SUCRA = 81; moderate-certainty evidence; secukinumab (versus placebo): RR 23.97, 95% CI 20.03 to 28.70, SUCRA = 75.4; high-certainty evidence; and brodalumab (versus placebo): RR 21.96, 95% CI 18.17 to 26.53, SUCRA = 68.7; moderate-certainty evidence. Conservative interpretation is warranted for the results for bimekizumab (as well as tyrosine kinase 2 inhibitor, acitretin, ciclosporin, fumaric acid esters, and methotrexate), as these drugs, in the NMA, have been evaluated in few trials. We found no significant difference between any of the interventions and the placebo for the risk of SAEs. Nevertheless, the SAE analyses were based on a very low number of events with low to very low certainty for just under half of the treatment estimates in total, and moderate for the others. Thus, the results have to be viewed with caution and we cannot be sure of the ranking. For other efficacy outcomes (PASI 75 and Physician Global Assessment (PGA) 0/1) the results were very similar to the results for PASI 90. Information on quality of life was often poorly reported and was absent for several of the interventions.

AUTHORS' CONCLUSIONS

Our review shows that compared to placebo, the biologics infliximab, ixekizumab, risankizumab, bimekizumab, guselkumab, secukinumab and brodalumab were the best choices for achieving PASI 90 in people with moderate-to-severe psoriasis on the basis of moderate- to high-certainty evidence (low-certainty evidence for bimekizumab). This NMA evidence is limited to induction therapy (outcomes were measured from 8 to 24 weeks after randomisation) and is not sufficient for evaluation of longer-term outcomes in this chronic disease. Moreover, we found low numbers of studies for some of the interventions, and the young age (mean age of 45 years) and high level of disease severity (PASI 20 at baseline) may not be typical of patients seen in daily clinical practice. Another major concern is that short-term trials provide scanty and sometimes poorly-reported safety data and thus do not provide useful evidence to create a reliable risk profile of treatments. Indeed, we found no significant difference in the assessed interventions and placebo in terms of SAEs, but the evidence for all the interventions was of very low to moderate quality. In order to provide long-term information on the safety of the treatments included in this review, it will also be necessary to evaluate non-randomised studies and postmarketing reports released from regulatory agencies. In terms of future research, randomised trials comparing directly active agents are necessary once high-quality evidence of benefit against placebo is established, including head-to-head trials amongst and between conventional systemic and small molecules, and between biological agents (anti-IL17 versus anti-IL23, anti-IL23 versus anti-IL12/23, anti-TNF alpha versus anti-IL12/23). Future trials should also undertake systematic subgroup analyses (e.g. assessing biological-naïve participants, baseline psoriasis severity, presence of psoriatic arthritis, etc.). Finally, outcome measure harmonisation is needed in psoriasis trials, and researchers should look at the medium- and long-term benefit and safety of the interventions and the comparative safety of different agents. Editorial note: This is a living systematic review. Living systematic reviews offer a new approach to review updating, in which the review is continually updated, incorporating relevant new evidence as it becomes available. Please refer to the Cochrane Database of Systematic Reviews for the current status of this review.

Systemic pharmacological treatments for chronic plaque psoriasis: a network meta-analysis

BACKGROUND

Psoriasis is an immune-mediated disease for which some people have a genetic predisposition. The condition manifests in inflammatory effects on either the skin or joints, or both, and it has a major impact on quality of life. Although there is currently no cure for psoriasis, various treatment strategies allow sustained control of disease signs and symptoms. Several randomised controlled trials (RCTs) have compared the efficacy of the different systemic treatments in psoriasis against placebo. However, the relative benefit of these treatments remains unclear due to the limited number of trials comparing them directly head to head, which is why we chose to conduct a network meta-analysis.

OBJECTIVES

To compare the efficacy and safety of conventional systemic agents (acitretin, ciclosporin, fumaric acid esters, methotrexate), small molecules (apremilast, tofacitinib, ponesimod), anti-TNF alpha (etanercept, infliximab, adalimumab, certolizumab), anti-IL12/23 (ustekinumab), anti-IL17 (secukinumab, ixekizumab, brodalumab), anti-IL23 (guselkumab, tildrakizumab), and other biologics (alefacept, itolizumab) for patients with moderate to severe psoriasis and to provide a ranking of these treatments according to their efficacy and safety.

SEARCH METHODS

We searched the following databases to December 2016: the Cochrane Skin Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, and LILACS. We also searched five trials registers and the U.S. Food and Drug Administration (FDA) and European Medicines Agency (EMA) reports. We checked the reference lists of included and excluded studies for further references to relevant RCTs. We searched the trial results databases of a number of pharmaceutical companies and handsearched the conference proceedings of a number of dermatology meetings.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of systemic and biological treatments in adults (over 18 years of age) with moderate to severe plaque psoriasis or psoriatic arthritis whose skin had been clinically diagnosed with moderate to severe psoriasis, at any stage of treatment, in comparison to placebo or another active agent.

DATA COLLECTION AND ANALYSIS

Three groups of two review authors independently undertook study selection, data extraction, 'Risk of bias' assessment, and analyses. We synthesised the data using pair-wise and network meta-analysis (NMA) to compare the treatments of interest and rank them according to their effectiveness (as measured by the Psoriasis Area and Severity Index score (PASI) 90) and acceptability (the inverse of serious adverse effects). We assessed the certainty of the body of evidence from the NMA for the two primary outcomes, according to GRADE; we evaluated evidence as either very low, low, moderate, or high. We contacted study authors when data were unclear or missing.

MAIN RESULTS

We included 109 studies in our review (39,882 randomised participants, 68% men, all recruited from a hospital). The overall average age was 44 years; the overall mean PASI score at baseline was 20 (range: 9.5 to 39). Most of these studies were placebo controlled (67%), 23% were head-to-head studies, and 10% were multi-armed studies with both an active comparator and placebo. We have assessed all treatments listed in the objectives (19 in total). In all, 86 trials were multicentric trials (two to 231 centres). All of the trials included in this review were limited to the induction phase (assessment at less than 24 weeks after randomisation); in fact, all trials included in the network meta-analysis were measured between 12 and 16 weeks after randomisation. We assessed the majority of studies (48/109) as being at high risk of bias; 38 were assessed as at an unclear risk, and 23, low risk.Network meta-analysis at class level showed that all of the interventions (conventional systemic agents, small molecules, and biological treatments) were significantly more effective than placebo in terms of reaching PASI 90.In terms of reaching PASI 90, the biologic treatments anti-IL17, anti-IL12/23, anti-IL23, and anti-TNF alpha were significantly more effective than the small molecules and the conventional systemic agents. Small molecules were associated with a higher chance of reaching PASI 90 compared to conventional systemic agents.At drug level, in terms of reaching PASI 90, all of the anti-IL17 agents and guselkumab (an anti-IL23 drug) were significantly more effective than the anti-TNF alpha agents infliximab, adalimumab, and etanercept, but not certolizumab. Ustekinumab was superior to etanercept. No clear difference was shown between infliximab, adalimumab, and etanercept. Only one trial assessed the efficacy of infliximab in this network; thus, these results have to be interpreted with caution. Tofacitinib was significantly superior to methotrexate, and no clear difference was shown between any of the other small molecules versus conventional treatments.Network meta-analysis also showed that ixekizumab, secukinumab, brodalumab, guselkumab, certolizumab, and ustekinumab outperformed other drugs when compared to placebo in terms of reaching PASI 90: the most effective drug was ixekizumab (risk ratio (RR) 32.45, 95% confidence interval (CI) 23.61 to 44.60; Surface Under the Cumulative Ranking (SUCRA) = 94.3; high-certainty evidence), followed by secukinumab (RR 26.55, 95% CI 20.32 to 34.69; SUCRA = 86.5; high-certainty evidence), brodalumab (RR 25.45, 95% CI 18.74 to 34.57; SUCRA = 84.3; moderate-certainty evidence), guselkumab (RR 21.03, 95% CI 14.56 to 30.38; SUCRA = 77; moderate-certainty evidence), certolizumab (RR 24.58, 95% CI 3.46 to 174.73; SUCRA = 75.7; moderate-certainty evidence), and ustekinumab (RR 19.91, 95% CI 15.11 to 26.23; SUCRA = 72.6; high-certainty evidence).We found no significant difference between all of the interventions and the placebo regarding the risk of serious adverse effects (SAEs): the relative ranking strongly suggested that methotrexate was associated with the best safety profile regarding all of the SAEs (RR 0.23, 95% CI 0.05 to 0.99; SUCRA = 90.7; moderate-certainty evidence), followed by ciclosporin (RR 0.23, 95% CI 0.01 to 5.10; SUCRA = 78.2; very low-certainty evidence), certolizumab (RR 0.49, 95% CI 0.10 to 2.36; SUCRA = 70.9; moderate-certainty evidence), infliximab (RR 0.56, 95% CI 0.10 to 3.00; SUCRA = 64.4; very low-certainty evidence), alefacept (RR 0.72, 95% CI 0.34 to 1.55; SUCRA = 62.6; low-certainty evidence), and fumaric acid esters (RR 0.77, 95% CI 0.30 to 1.99; SUCRA = 57.7; very low-certainty evidence). Major adverse cardiac events, serious infections, or malignancies were reported in both the placebo and intervention groups. Nevertheless, the SAEs analyses were based on a very low number of events with low to very low certainty for just over half of the treatment estimates in total, moderate for the others. Thus, the results have to be considered with caution.Considering both efficacy (PASI 90 outcome) and acceptability (SAEs outcome), highly effective treatments also had more SAEs compared to the other treatments, and ustekinumab, infliximab, and certolizumab appeared to have the better trade-off between efficacy and acceptability.Regarding the other efficacy outcomes, PASI 75 and Physician Global Assessment (PGA) 0/1, the results were very similar to the results for PASI 90.Information on quality of life was often poorly reported and was absent for a third of the interventions.

AUTHORS' CONCLUSIONS

Our review shows that compared to placebo, the biologics ixekizumab, secukinumab, brodalumab, guselkumab, certolizumab, and ustekinumab are the best choices for achieving PASI 90 in people with moderate to severe psoriasis on the basis of moderate- to high-certainty evidence. At class level, the biologic treatments anti-IL17, anti-IL12/23, anti-IL23, and anti-TNF alpha were significantly more effective than the small molecules and the conventional systemic agents, too. This NMA evidence is limited to induction therapy (outcomes were measured between 12 to 16 weeks after randomisation) and is not sufficiently relevant for a chronic disease. Moreover, low numbers of studies were found for some of the interventions, and the young age (mean age of 44 years) and high level of disease severity (PASI 20 at baseline) may not be typical of patients seen in daily clinical practice.Another major concern is that short-term trials provide scanty and sometimes poorly reported safety data and thus do not provide useful evidence to create a reliable risk profile of treatments. Indeed, we found no significant difference in the assessed interventions and placebo in terms of SAEs. Methotrexate appeared to have the best safety profile, but as the evidence was of very low to moderate quality, we cannot be sure of the ranking. In order to provide long-term information on the safety of the treatments included in this review, it will be necessary to evaluate non-randomised studies and postmarketing reports released from regulatory agencies as well.In terms of future research, randomised trials comparing directly active agents are necessary once high-quality evidence of benefit against placebo is established, including head-to-head trials amongst and between conventional systemic and small molecules, and between biological agents (anti-IL17 versus anti-IL23, anti-IL23 versus anti-IL12/23, anti-TNF alpha versus anti-IL12/23). Future trials should also undertake systematic subgroup analyses (e.g. assessing biological-naïve patients, baseline psoriasis severity, presence of psoriatic arthritis, etc.). Finally, outcome measure harmonisation is needed in psoriasis trials, and researchers should look at the medium- and long-term benefit and safety of the interventions and the comparative safety of different agents.

Tumor Targeting with Novel 6-Substituted Pyrrolo [2,3-d] Pyrimidine Antifolates with Heteroatom Bridge Substitutions via Cellular Uptake by Folate Receptor α and the Proton-Coupled Folate Transporter and Inhibition of de Novo Purine Nucleotide Biosynthesis

Targeted antifolates with heteroatom replacements of the carbon vicinal to the phenyl ring in 1 by N (4), O (8), or S (9), or with N-substituted formyl (5), acetyl (6), or trifluoroacetyl (7) moieties, were synthesized and tested for selective cellular uptake by folate receptor (FR) α and β or the proton-coupled folate transporter. Results show increased in vitro antiproliferative activity toward engineered Chinese hamster ovary cells expressing FRs by 4-9 over the CH2 analogue 1. Compounds 4-9 inhibited de novo purine biosynthesis and glycinamide ribonucleotide formyltransferase (GARFTase). X-ray crystal structures for 4 with FRα and GARFTase showed that the bound conformations of 4 required flexibility for attachment to both FRα and GARFTase. In mice bearing IGROV1 ovarian tumor xenografts, 4 was highly efficacious. Our results establish that heteroatom substitutions in the 3-atom bridge region of 6-substituted pyrrolo[2,3-d]pyrimidines related to 1 provide targeted antifolates that warrant further evaluation as anticancer agents.

Methotrexate efficacy, but not its intolerance, is associated with the dose and route of administration

BACKGROUND

There is a lack of published evidence on the importance of methotrexate (MTX) dose and route of administration on both its efficacy and adverse events in children with Juvenile Idiopathic Arthritis (JIA). We aimed to document our clinical practice based on the treat-to-target approach in order to support the concept that better therapeutic effect achieved with an optimal dose of parenteral MTX is associated with clinically acceptable adverse effects comparable to those reported for oral treatment.

METHODS

Study inclusion criteria were indication of new MTX therapy for active arthritis in confirmed JIA patients younger than 18 years. Eligible patients were evaluated prospectively every 3 months for 1 year using standardized instruments for treatment response (American College of Rheumatology Pediatric (ACRPedi) response, Juvenile Arthritis Disease Activity Score (JADAS) 71, Clinically Inactive Disease (CID)) and adverse events (laboratory monitoring, Methotrexate Intolerance Severity Score (MISS)). MTX responders had to achieve at least ACRPedi 70 response. MTX intolerance was defined by MISS ≥ 6.

RESULTS

In 45/55 patients (81.8 %) MTX was started as subcutaneous injection. The initial median weekly dose was 14.4 mg/m(2) in parenteral and 11.7 mg/m(2) in oral administration. MTX therapy was effective in the level of ACRpedi70 and CID in 50.9 % and 30.9 % of patients at month 6 and in 70.9 % and 56.4 % after 12 months of the treatment, respectively. MTX intolerance at 6 and 12 months was noted in 25.5 % and 30.6 %, respectively. Management of intolerance included change in the dose and/or route of administration, education and councelling. Adverse events led to MTX withdrawal in 5 patients (9 %) due to toxicity (n = 3) and intolerance (n = 2). We did not find any significant predictive factors for either MTX therapeutic response or intolerance.

CONCLUSION

Subcutaneous MTX weekly dose around 15 mg/m(2) is associated not only with a high response rate within the first 12 months of treatment, but also with a relatively low rate of significant adverse effects that would lead to the treatment termination. It allows early recognition of MTX non-responders and addition of biologic therapy. Sustainability of therapeutic effect and longer-term evolution of adverse events will be addressed by an ongoing extension of the study.

Potential drug interactions associated with glycyrrhizin and glycyrrhetinic acid

Glycyrrhizin (GZ), the main active component of licorice, is a widely used therapeutic in the clinic. Depending on the disease, the treatment may involve a long course of high dose GZ. Another component of licorice, glycyrrhetinic acid (GA), is the main active metabolite of GZ and is thought to be responsible for the majority of the pharmacological properties of GZ. Therefore, GZ and GA are both used for therapeutic purposes. In addition, GZ and GA are also widely used to sweeten and flavor foods. Due to this widespread, multifaceted use of these substances, potential drug interactions with GZ and GA have recently gained attention. Along these lines, this review covers the known effects of GZ and GA on drug-metabolizing enzymes and efflux transporters. We conclude that both GZ and GA may have an effect on the activity of CYPs. For example, GZ may induce CYP3A activity through activation of PXR. Also, GZ and GA may affect glucuronidation in rats and humans. Furthermore, 18β-GA is a potent inhibitor of P-gp, while GZ and GA are inhibitors of MRP1, MRP2 and BCRP. The pharmacokinetics and pharmacodynamics of many medications may be altered when used concurrently with GZ or GA, which is also covered in this review. Overall, GZ, GA or related products should be taken with caution when taken with additional medications due to the possible drug interactions.

Glycyrrhizic acid in the treatment of liver diseases: literature review

Glycyrrhizic acid (GA) is a triterpene glycoside found in the roots of licorice plants (Glycyrrhiza glabra). GA is the most important active ingredient in the licorice root, and possesses a wide range of pharmacological and biological activities. GA coupled with glycyrrhetinic acid and 18-beta-glycyrrhetic acid was developed in China or Japan as an anti-inflammatory, antiviral, and antiallergic drug for liver disease. This review summarizes the current biological activities of GA and its medical applications in liver diseases. The pharmacological actions of GA include inhibition of hepatic apoptosis and necrosis; anti-inflammatory and immune regulatory actions; antiviral effects; and antitumor effects. This paper will be a useful reference for physicians and biologists researching GA and will open the door to novel agents in drug discovery and development from Chinese herbs. With additional research, GA may be more widely used in the treatment of liver diseases or other conditions.

Methotrexate in systemic lupus erythematosus: a systematic review of its efficacy

OBJECTIVE

The objective of this review is to evaluate the evidence for efficacy of methotrexate (MTX) in systemic lupus erythematosus (SLE).

METHODS

A comprehensive, computerized search was performed in MEDLINE (PubMed), EMBASE and the Cochrane Controlled Trials registry to screen for studies that examined the efficacy of MTX in adult SLE patients. The Jadad scoring system was used to assess study quality, and data were pooled using the random effects model.

RESULTS

Of the 53 articles that were identified, 44 were excluded. Nine studies (including three randomized controlled and six observational) were eligible for inclusion. All of the included studies predominantly involved patients with arthritis or mucocutaneous features. There was significant reduction of the SLE Disease Activity Index (SLEDAI) among MTX-treated patients when compared with controls (p = 0.001, odds ratio (OR) 0.444, 95% confidence interval (CI) 0.279 to 0.707). There was also significant reduction in the average dose of corticosteroids among MTX-treated patients when compared with controls (p = 0.001, OR 0.335, 95% CI 0.202 to 0.558). The effect of MTX on laboratory and serological markers, including erythrocyte sedimentation rate, anti-dsDNA and complement levels (C3 and C4), could not be determined because of the limited numbers of controlled trials.

CONCLUSION

The use of MTX is associated with significant reductions in SLEDAI and the average dose of corticosteroids in adult patients with SLE.

Drug repositioning in the treatment of malaria and TB

The emergence and spread of drug resistance in the malaria parasite Plasmodium falciparum as well as multi- and extremely drug-resistant forms of Mycobacterium tuberculosis, the causative agent of TB, could hamper the control of these diseases. For instance, there are indications that the malaria parasite is becoming resistant to artemisinin derivatives, drugs that form the backbone of antimalarial combination therapy. Likewise, Mycobacterium tuberculosis strains that are multidrug-resistant or extremely drug-resistant to first- and second-line drugs have been associated with increased mortality. Thus, more than ever, new antimalarials and anti-TB drugs are needed. One of the strategies to discover new drugs is to reposition or repurpose existing drugs, thus reducing the cost and time of drug development. In this review, we discuss how this concept has been used in the past to discover antimalarial and anti-TB drugs, and summarize strategies that can lead to the discovery and development of new drugs.

A phase I trial to evaluate the safety and pharmacokinetics of low-dose methotrexate as an anti-malarial drug in Kenyan adult healthy volunteers

Background

Previous investigations indicate that methotrexate, an old anticancer drug, could be used at low doses to treat malaria. A phase I evaluation was conducted to assess the safety and pharmacokinetic profile of this drug in healthy adult male Kenyan volunteers.

Methods

Twenty five healthy adult volunteers were recruited and admitted to receive a 5 mg dose of methotrexate/day/5 days. Pharmacokinetics blood sampling was carried out at 2, 4, 6, 12 and 24 hours following each dose. Nausea, vomiting, oral ulcers and other adverse events were solicited during follow up of 42 days.

Results

The mean age of participants was 23.9 ± 3.3 years. Adherence to protocol was 100%. No grade 3 solicited adverse events were observed. However, one case of transiently elevated liver enzymes, and one serious adverse event (not related to the product) were reported. The maximum concentration (C_max) was 160-200 nM and after 6 hours, the effective concentration (C_eff) was <150 nM.

Conclusion

Low-dose methotraxate had an acceptable safety profile. However, methotrexate blood levels did not reach the desirable C_eff of 250-400-nM required to clear malaria infection in vivo. Further dose finding and safety studies are necessary to confirm suitability of this drug as an anti-malarial agent.

Methotrexate is highly potent against pyrimethamine-resistant Plasmodium vivax

Resistance of vivax malaria to treatment with antifolates, such as pyrimethamine (Pyr), is spreading as mutations in the dihydrofolatereductase (dhfr) genes are selected and disseminated. We tested the antitumor drug methotrexate (MTX), a potent competitive inhibitor of dhfr, against 11 Plasmodium vivax isolates ex vivo, 10 of which had multiple dhfr mutations associated with Pyr resistance. Despite high-grade resistance to Pyr (median 50% inhibitory concentration [IC₅₀], 13,345 nM), these parasites were all highly susceptible to MTX (median IC₅₀, 2.6 nM). Given its potency against Pyr-resistant P. vivax, the antimalarial potential of MTX deserves further investigation.

677TT Genotype Is Associated with Elevated Risk of Methotrexate (MTX) Toxicity in Juvenile Idiopathic Arthritis: Treatment Outcome, Erythrocyte Concentrations of MTX and Folates, and MTHFR Polymorphisms

Objective.

To investigate whether methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C polymorphisms and erythrocyte concentration of methotrexate (EMTX) could serve as predictors of methotrexate (MTX) efficacy and toxicity in patients with juvenile idiopathic arthritis (JIA).

Methods.

Genetic analyses and EMTX and folate assessment were performed in 69 patients with JIA aged 2.5–19.6 years (30 male) treated with MTX using a dose-escalation protocol and classified as full responders (disease inactivity; n = 51) or nonresponders (< 30% improvement in pediatric American College of Rheumatology-30 criteria while receiving ≥ 15 mg/m2/week parenteral MTX for at least 3 months; n = 18).

Results.

Nonresponders were treated with the higher median MTX dose (17.2 vs 12.6 mg/m2/week; p < 0.0001) and accumulated more EMTX (217 vs 106 nmol/l; p < 0.02) and erythrocyte folates (763 vs 592 nmol/l; p = 0.052) than responders. Analysis of MTHFR allele and genotype frequencies in relation to response failed to detect association. The frequency of any adverse effect was 29.4% in responders and 33.3% in nonresponders (p = 0.77). The frequency of 677T allele was elevated in patients with adverse effects (52.4% vs 20.9%; OR 3.88, 95% CI 1.8–8.6, p < 0.002). The probability of any adverse effect was significantly higher in patients with 677TT compared to the 677CC genotype (OR 55.5, 95% CI 2.9–1080, p < 0.001).

Conclusion.

MTHFR genotyping may have a predictive value for the risk of MTX-associated toxicity in patients with JIA. Despite the lack of therapeutic effect, nonresponders accumulated adequate concentrations of EMTX.

Anticancer agents against malaria: time to revisit?

The emergence of artemisinin resistance could adversely impact the current strategy for malaria treatment; thus, new drugs are urgently needed. A possible approach to developing new antimalarials is to find new uses for old drugs. Some anticancer agents such as methotrexate and trimetrexate are active against malaria. However, they are commonly perceived to be toxic and thus not suitable for malaria treatment. In this opinion article, we examine how the toxicity of anticancer agents is just a matter of dose or ‘only dose makes the poison’, as coined in Paracelsus’ law. Thus, the opportunity exists to discover new antimalarials using the anticancer pharmacopoeia.

Glycyrrhizin and licorice significantly affect the pharmacokinetics of methotrexate in rats

Glycyrrhizin (GZ) and licorice (root of Glycyrrhiza uralensis) are worldwide food additives and important oriental phytomedicines. This study investigated the biological fate of GZ by orally giving GZ and licorice decoction (LD) to rats. The serum concentrations of GZ and glycyrrhetic acid (GA) were determined by high performance liquid chromatography. The results showed that GZ was not detected and GA was present in serum until 3 days postdosing of GZ and LD. To evaluate the effects of GZ and licorice on the pharmacokinetics of methotrexate (MTX), an important immunosuppressant with a narrow therapeutic window, rats were orally given MTX with and without GZ and LD in different dosage regimens. The serum MTX concentration was determined by fluorescence polarization immunoassay. The results revealed that the AUC and MRT of MTX were significantly increased by GZ and LD. In conclusion, the concurrent use of GZ or licorice with MTX should be with caution.

The applications of biomarkers in early clinical drug development to improve decision-making processes

Selecting and evaluating biomarkers in drug discovery and early drug development can substantially shorten clinical development time or the time to reach a critical decision point in exploratory drug development. Critical decisions such as candidate selection, early proof of concept/principle, dose ranging, development risks, and patient stratification are based on the appropriate measurements of biomarkers that are biologically and/or clinically validated. The use of biomarkers helps to streamline clinical development by determining whether the drug is reaching and affecting the molecular target in humans, delivering findings that are comparable to preclinical data, and by providing a measurable endpoint that predicts desired or undesired clinical effects and will increase the success rate in the confirmatory stage of clinical development. Appropriateness of biomarkers depends on the stage of development, development strategy, and the nature of the medical indication. Even if a biomarker fails in the validation process there may be still a benefit of having used it. More knowledge about pathophysiology of the disease and the drug has been obtained. Different levels of validation exist at different development phases. Biomarkers are perhaps most useful in the early phase of clinical development when measurement of clinical endpoints may be too time-consuming or cumbersome to provide timely proof of concept or dose-ranging information. Examples of biomarkers are illustrated for the development of new drugs in variant cardiovascular, pulmonary, and CNS diseases.