Get With the Guidelines on MS Imaging by Leveraging Peer Learning.

OBJECTIVES: To achieve consensus on the performance, interpretation and reporting of MS imaging according to up-to-date guidelines using the Peer Learning Methodology. MATERIALS AND METHODS: We utilized the Peer Learning Methodology to engage our clinical and radiology colleagues, review the current guidelines, acheive consensus on imaging techniques and reporting standards. After implementing changes, we collected radiologist feedback on the impact of the optimized images on their interpretation. RESULTS: Survey responders indicated a strong preference for the new protocol in terms of overall image quality, individual lesions conspicuity and confidence in the ability to detect an MS lesion. The new protocol was preferred for both MS diagnosis and MS surveillance in 25 of 28 responses. CONCLUSION: The Peer Learning Methodology is an effective tool to standardize and improve MR imaging quality, interpretation and reporting for Multiple Sclerosis in accordance with current guidelines.

Minocycline Extended-Release Comparison with Doxycycline for the Treatment of Rosacea: A Randomized, Head-to-Head, Clinical Trial.

OBJECTIVE: Minocycline efficacy for the treatment of papulopustular rosacea (PPR) has not been evaluated in clinical trials at levels demonstrated to stay below the antimicrobial threshold. We assessed the efficacy, safety, and dose response of DFD-29, a minocycline extended-release oral capsule. Two studies are reported (NCT03340961). METHODS: A single-center open-label, three-arm, Phase I pharmacokinetic study randomized 24 healthy subjects aged 18 to 45 years to receive 21 days of once-daily dosing with DFD-29 40 or 20mg, or doxycycline 40mg. Blood samples were collected over 24 hours on Days 1 and 21 to plot mean plasma concentration levels. A multicenter Phase II clinical trial randomized 205 subjects with mild-to-severe PPR 1:1:1:1 to receive once-daily DFD-29 40 or 20mg, doxycycline 40mg, or placebo for 16 weeks. Co-primary endpoints were the proportion of subjects achieving treatment success (IGA grade 0 or 1 and ≥2-grade improvement) at Week 16, and a reduction in total inflammatory lesion count at Week 16. RESULTS: Pharmacokinetic analysis demonstrated that minocycline plasma levels of DFD-29 40mg were approximately half those of doxycycline 40mg after 21 days, with DFD-29 20mg even lower, demonstrating a dose response. In the Phase II trial, DFD-29 40mg met both co-primary endpoints, achieving IGA treatment success in 66.0 percent subjects versus 11.5 percent placebo (p<0.0001), 31.9 percent DFD-29 20mg (p=0.007), and 33.3 percent doxycycline 40mg (p<0.0010), and a mean reduction in lesion counts of -19.2 versus -7.3 placebo (p<0.0001), -12.6 DFD-29 20mg (p=0.0070), and -10.5 doxycycline 40mg (p=0.0004). LIMITATIONS: MIC values and plasma concentrations shown for antibacterial threshold data are mean values; fast absorbers/slow metabolizers could exceed the threshold, causing resistance selection pressure. CONCLUSION: DFD-29 40mg demonstrated significantly greater efficacy than placebo, DFD-29 20mg, and doxycycline 40mg at plasma concentrations predicted to be below the antimicrobial threshold for the treatment of PPR.

Real-time feedback control of voice in cochlear implant recipients.

OBJECTIVES: To evaluate feedback-dependent vocal control in cochlear implant patients using pitch-shifted auditory feedback. METHODS: Twenty-three CI recipients with at least 6 months of implant experience were enrolled. Vocal recordings were performed while subjects repeated the vowel /e/ and vocal signals were altered in real-time using a digital effects processor to introduce a pitch-shift, presented back to subjects using headphones. Recordings were analyzed to determine pitch changes following the pitch-shifted feedback, and results compared to the magnitude of the shift as well as patient demographics. RESULTS: Consistent with previous results, CI patients' voices had higher pitches with their implant turned off, a change explainable by increases in vocal loudness without the CI. CI patients rapidly compensated for pitch-shifted feedback by changing their vocal pitch, but only for larger shifts. Considerable inter-subject variability was present, and weakly correlated with the duration of implant experience and implant sound thresholds. CONCLUSIONS: CI patients, like normal hearing individuals, are capable of real-time feedback-dependent control of their vocal pitch. However, CI patients are less sensitive to small feedback changes, possibly a result of courser CI frequency precision, and may explain poorer than normal vocal control in these patients. LEVEL OF EVIDENCE: Level 3b.

The effect of food and formulation on the population pharmacokinetics of cholesteryl ester transferase protein inhibitor DRL-17822 in healthy male volunteers.

We aimed to characterise the population pharmacokinetics of cholesteryl ester transferase protein inhibitor DRL-17822 in healthy males and explore the effect of food and formulation on the oral absorption of DRL-17822 in 4 phase I studies. DRL-17822 was dosed orally (2-1000 mg) in 2 different drug formulations (nanocrystal formulation and amorphous solid dispersion formulation) after either an overnight fast, or a low-fat, continental or high-fat breakfast. A 2-compartment model with 6 transit absorption compartments best characterised the data. Additionally, a strong interaction of food and formulation on bioavailability was observed and parsimoniously characterised in the model by binning combinations of food state and formulation with similar bio-availabilities. The final model adequately characterised the pharmacokinetic data of DRL-17822 in healthy males including the complex interaction of food and drug formulation. The amorphous solid dispersion formulation has a lower food effect on bioavailability compared with the nanocrystal formulation.

Bioavailability, Pharmacokinetics, and Transepidermal Water Loss of Short Contact Tazarotene Lotion 0.1% Versus Tazarotene (Tazorac®) Cream 0.1.

Objective: Two clinical studies were conducted to 1) assess the pharmacokinetic (PK) properties of tazarotene and tazarotenic acid in DFD-03 lotion (a 1-minute, short-contact formulation for the topical treatment of acne vulgaris) and tazarotene cream 0.1% and 2) to evaluate transepidermal water loss (TEWL) with DFD-03 lotion, tazarotene gel (0.1%), or vehicle. Design: The PK study included a single-center, randomized, multiple-dose, laboratory-blinded, open-label, parallel-design, and the TEWL study included a multiple-dose, within-subject comparison design. Participants: The PK study included healthy adult men aged 18 to 40 years (n=43), and the TEWL study included healthy adults, male or female, aged 18 to 40 years (n=24). Measurements: PK was assessed via Cmax, AUC0-12, AUC0-24, Tmax, Cmin, Tmin, and fluctuation. TEWL was assessed via evaporimetry. Results: Tazarotene levels were very low due to rapid esterase hydrolysis to the primary active metabolite, tazarotenic acid. Tazarotenic acid AUC0-24 ratios (%) were at least two times higher when the test product was applied twice daily (Treatment-1) versus once daily (Treatment-2) on Days 7 and 14 (268.73% and 254.42%, respectively). Tazarotenic acid AUC0-24 ratios (%) were nearly 100 percent for Treatment-1 versus once-daily tazarotene cream 0.1% (Treatment-3) (99.36% and 83.21%, on Days 7 and 14, respectively). Starting on Day 7, DFD-03 lotion TEWL readings were significantly greater than vehicle (p≤0.05), except for on one study day. DFD-03 lotion TEWL readings were numerically greater (nonsignificant) than tazarotene gel. Conclusion: DFD-03 lotion was well-tolerated, increased TEWL when applied twice daily for one minute, and had a PK profile with similar overall exposure as compared with commercially available tazarotene formulations applied once daily for 12 hours.

Effect of Food on the Pharmacokinetics of 2 Formulations of DRL-17822, a Novel Selective Cholesteryl Ester Transfer Protein (CETP) Inhibitor, in Healthy Males.

DRL-17822 is a novel selective cholesteryl ester transfer protein inhibitor that showed an increased exposure, including an increase of >20-fold of maximum concentration and area under the plasma concentration-time curve from time zero to the time of the last quantifiable concentration, following a high-fat breakfast using a nanocrystal formulation. To reduce this effect of food, we generated an amorphous solid dispersion formulation. In this study, we compared the food effect of both formulations of DRL-17822 in a 2-part randomized, open-label, 4-way crossover study involving healthy adult males 18-45 years of age. In both parts of the study, 12 subjects received both formulations of DRL-17822 in both the fasted and fed states; a low-fat breakfast was provided in the first part and a high-fat breakfast in the second part. Compared to the nanocrystal formulation, the amorphous solid dispersion formulation substantially increased DRL-17822 exposure in the fasted state, including increased maximum concentration, area under the plasma concentration-time curve from time zero to the time of the last quantifiable concentration, and area under plasma concentration-time curve from time zero to infinity. Following a high-fat breakfast, DRL-17822 exposure was increased to a lesser extent in the amorphous solid dispersion formulation compared to the nanocrystal formulation (P < .001). Moreover, compared to the nanocrystal formulation the amorphous solid dispersion formulation caused a more pronounced increase in high-density lipoprotein in the fasted state. Consuming breakfast increased the effect of DRL-17822 on high-density lipoprotein. Taken together, our results indicate that by improving its formulation, DRL-17822 has a favorable exposure profile and therefore a more predictable food effect profile.

Control of speech and voice in cochlear implant patients.

OBJECTIVE: Hearing plays an important role in the learning and production of speech, but the benefits of cochlear implantation for such vocal control are unclear. Here, we present a perspective and review of recent work on the control of speech and voice following cochlear implantation. We further discuss insights provided on the mechanisms of normal vocal control and implications for future rehabilitative approaches. DATA SOURCES: Peer-reviewed articles on speech and voice production in cochlear implant patients were identified from PUBMED. Relevant articles were supplemented with selected publications describing normal vocal control mechanisms and behaviors. REVIEW METHODS: Publications that discussed speech and voice outcomes following cochlear implantation were chosen, with a focus on those presenting measurements of specific speech or voice parameters. RESULTS: Recent studies demonstrate that hearing restoration by cochlear implantation has significant effects on many aspects of voice and speech production. These include changes in vocal pitch and loudness, as well as improved control of both vowels and consonants. Despite these improvements, however, the speech of many implant recipients remains abnormal as compared to normal hearing individuals. Such differences likely result from the impoverished auditory feedback provided by the implant. CONCLUSIONS: Cochlear implants provide valuable insights into the role of hearing in vocal production. Although implants improve vocal production for most patients, there remains considerable room for future study and therapeutic improvement. Laryngoscope, 129:2158-2163, 2019.

Target site pharmacokinetics of doxycycline for rosacea in healthy volunteers is independent of the food effect.

AIMS: Doxycycline (DFD-09) oral capsules 40 mg are approved for the treatment of inflammatory lesions of rosacea. Unlike the food-induced lowering of doxycycline's peak plasma concentration (Cmax ), its exposure under fed conditions in the skin, the drug's target site for rosacea, is unknown. The present study explored the effect of food on the dermal pharmacokinetics of doxycycline. METHODS: The pharmacokinetics of doxycycline in the dermal interstitial fluid (d-ISF) and plasma of healthy volunteers were assessed in parallel groups under fed (n = 6) and fasting (n = 6) conditions during a 14-day once-daily treatment course with doxycycline oral capsules 40 mg (DFD-09). Sampling of d-ISF and plasma was performed on days 1, 10 (fasting group d-ISF only) and 14. RESULTS: Twelve subjects were randomized, and 11 analysed. No causally drug-related adverse events occurred. Dermal doxycycline exposures (Cmax and area under the curve) under the fed state were about 30% lower than under the fasting state at day 1 but were similar at steady state. In analogy to skin, plasma exposure showed no between-group difference at steady state. Accumulation ratios were higher in the skin than in plasma. Correcting for plasma protein binding (~90%), dermal doxycycline exposure was approximately threefold higher than unbound plasma exposure. CONCLUSIONS: At steady state, doxycycline concentrations in the skin of fed and fasting healthy volunteers were comparable. Doxycycline's efficacy in rosacea is possibly due to considerable dermal accumulation of unbound doxycycline and is independent of the effect of food.

Pharmacokinetics of DFN-15, a Novel Oral Solution of Celecoxib, Versus Celecoxib 400-mg Capsules: A Randomized Crossover Study in Fasting Healthy Volunteers.

BACKGROUND: COX-2 inhibitors can be effective for acute migraine, but none is supplied in a rapidly absorbed, ready-to-use oral liquid formulation. DFN-15, a novel oral liquid formulation of celecoxib, is being developed for the acute treatment of migraine with or without aura. Clinical studies with this formulation are ongoing. OBJECTIVES: The objectives of the present study were to compare the bioavailability of DFN-15 with that of the commercial formulation of celecoxib 400-mg oral capsules (Celebrex®) and to determine the dose proportionality of DFN-15 in healthy fasted volunteers. METHODS: This single-dose randomized crossover study in 16 healthy fasted volunteers evaluated the pharmacokinetics and relative bioavailability of DFN-15 at doses of 120, 180, and 240 mg against the commercial formulation of celecoxib 400-mg oral capsules and determined the dose proportionality of DFN-15. RESULTS: The maximum observed plasma concentrations (C max) of celecoxib after the administration of DFN-15 120, 180, and 240 mg (1062-1933 ng/ml) were higher than for the 400-mg oral capsules (611 ng/ml). The median time to peak concentration (T max) was within 1 h for DFN-15 and 2.5 h for the oral capsules. The pharmacokinetics of DFN-15 were dose proportional from 120 to 240 mg. Partial area under the plasma concentration-time curves (AUCs) from 15 min to 2 h for DFN-15 120 mg were at least threefold higher than for the oral capsules, and the relative bioavailability of DFN-15 was approximately 140% that of the oral capsules. DFN-15 was well tolerated, with no new or unexpected adverse events. CONCLUSIONS: Based on a faster rate of absorption and increased bioavailability, DFN-15 is being evaluated as an abortive medication for acute treatment in patients with migraine.

Pharmacokinetic Characterization and Dose Selection of a Novel Sumatriptan Nasal Spray Formulation, DFN-02.

This 3-way, single-dose, randomized crossover study evaluated the pharmacokinetics (PK) and dose proportionality of 5-, 10-, and 15-mg doses of intranasal sumatriptan (DFN-02) coformulated with a permeation enhancer (DDM) in 18 healthy adults. The objective was to determine which DFN-02 dose approximates the PK of a 6-mg dose of sumatriptan delivered via subcutaneous injection in the deltoid muscle of the arm. Sumatriptan plasma concentrations peaked with DFN-02 between 10 and 15 minutes postdose, declining thereafter, with a t1/2 of about 2.5 hours; mean Cmax and AUC0-∞ values increased linearly across doses. After DFN-02 doses of 5, 10, and 15 mg, mean Cmax was 40.7 ± 14.2, 71.2  ±  22.1, and 101.0  ±  49.5 ng/mL, and mean AUC0-∞ was 49.9  ±  20.6, 87.1  ± 31.2, and 120.5  ± 53.3 ng·h/mL, respectively. The increase in sumatriptan bioavailability was less than dose-proportional among the DFN-02 doses studied. Based on the established PK of a 6-mg subcutaneous sumatriptan injection (mean Tmax ,  12 minutes; mean Cmax ,  74  ± 15 ng/mL in the deltoid area of the arm) and the peak and time to peak sumatriptan concentrations of the DFN-02 doses tested, a 10-mg dose of DFN-02 was found to be the closest match. Overall, DFN-02 was well tolerated at doses of 5 to 15 mg, and no new safety concerns were identified.

A Randomized Trial Comparing the Pharmacokinetics, Safety, and Tolerability of DFN-02, an Intranasal Sumatriptan Spray Containing a Permeation Enhancer, With Intranasal and Subcutaneous Sumatriptan in Healthy Adults.

OBJECTIVE/BACKGROUND: Intranasal sumatriptan (Imitrex® ) may be an alternative for patients who refuse injections and cannot tolerate oral agents, but due to low bioavailability and slow absorption, the clinical utility of the currently marketed formulation is limited, highlighting an unmet need for an effective non-oral migraine medication with a rapid onset of action. To overcome the slow absorption profile associated with intranasal administration, we evaluated the impact of 1-O-n-Dodecyl-ß-D-Maltopyranoside (DDM, Intravail A-3™), a permeation enhancer, on sumatriptan's pharmacokinetic profile by comparing the pharmacokinetic characteristics of two commercial sumatriptan products, 4 mg subcutaneous and 6 mg subcutaneous in healthy adults, with DFN-02 - a novel intranasal agent comprised of sumatriptan 10 mg plus 0.20% DDM. We also determined the pharmacokinetic characteristics of DDM and evaluated its safety and tolerability. METHODS: We conducted two studies: a randomized, three-way crossover study comparing monodose and multidose devices for delivery of single doses of DFN-02 with commercially available intranasal sumatriptan 20 mg in 18 healthy, fasted adults, and an open-label, randomized, single-dose, three-way crossover bioavailability study comparing DFN-02 with 4 mg and 6 mg subcutaneous sumatriptan in 78 healthy, fasted adults. In the study comparing DFN-02 with IN sumatriptan, subjects received a single dose of DFN-02 (sumatriptan 10 mg plus DDM 0.20%) via monodose and multidose delivery systems with at least 5 days between treatments. In the comparison with SC sumatriptan, subjects received a single dose of each treatment with at least 3 days between treatments. In both studies, blood was sampled for pharmacokinetic evaluation of sumatriptan and DDM through 24 hours post-dose; safety and tolerability were monitored throughout. RESULTS: In the comparison with commercially available intranasal sumatriptan 20 mg, DFN-02 had a more rapid absorption profile; tmax was 15 minutes for DFN-02 monodose, 10.2 minutes for DFN-02 multidose, and 2.0 hours for commercially available intranasal sumatriptan 20 mg. Compared with 4 and 6 mg subcutaneous sumatriptan, DFN-02's median tmax (10 minutes) was significantly earlier (15 minutes; P < .0001). Mean sumatriptan exposure metrics were similar for DFN-02 and 4 mg sumatriptan: AUC0-2 : 35.12 and 44.82 ng*hour/mL, respectively; AUC0-∞ : 60.70 and 69.21 ng*hour/mL, respectively; Cmax : 51.79 and 49.07 ng/mL, respectively. With 6 mg subcutaneous sumatriptan, these exposure metrics were about 50% larger (AUC0-2 : 67.17 ng*hour/mL; AUC0-∞ : 103.78 ng*hour/mL; Cmax : 72.75 ng/mL). Inter-subject variability of AUC0-2 , AUC0-∞ , and Cmax was 42-58% for DFN-02, 15-22% for 4 mg subcutaneous sumatriptan, and 15-25% for 6 mg subcutaneous sumatriptan. DDM exposure was low (mean Cmax : 1.63 ng/mL), tmax was 30 minutes, and it was undetectable by 4 hours. There were no serious adverse events, discontinuations due to adverse events, or remarkable findings for vital signs, physical examinations (including nasal and injection site examinations), or clinical laboratory assessments. The overall incidence of adverse events was comparable across treatments, and all treatment-related events were mild in severity. Adverse events occurring in ≥10% of subjects were dysgeusia (19%), headache (18%), nausea (15%), paresthesia (15%), and dizziness (12%). CONCLUSIONS: In healthy subjects, DFN-02, an intranasal spray containing 10 mg sumatriptan plus DDM, had a more rapid absorption profile than commercially available intranasal sumatriptan 20 mg, and systemic exposure from a single-dose administration of DFN-02 was similar to 4 mg SC sumatriptan and two-thirds that of 6 mg SC sumatriptan. With DFN-02, plasma sumatriptan peaked 5 minutes earlier than with both subcutaneous formulations. Systemic exposure to sumatriptan was similar with DFN-02 and 4 mg subcutaneous sumatriptan; both yielded lower systemic exposure than 6 mg subcutaneous sumatriptan. Systemic exposure to DFN-02's excipient DDM was short-lived. DFN-02's safety and tolerability appear to be comparable to subcutaneous sumatriptan. Addition of a permeation enhancer improved the absorption profile compared with commercially available intranasal sumatriptan 20 mg.

The effect of weight, body mass index, age, sex, and race on plasma concentrations of subcutaneous sumatriptan: a pooled analysis.

OBJECTIVE/BACKGROUND: Factors such as body size (weight and body mass index [BMI]), age, sex, and race might influence the clinical response to sumatriptan. We evaluated the impact of these covariates on the plasma concentration (Cp) profile of sumatriptan administered subcutaneously. METHODS: We conducted three pharmacokinetic studies of subcutaneous sumatriptan in 98 healthy adults. Sumatriptan was administered subcutaneously (236 administrations) as either DFN-11 3 mg, a novel 0.5 mL autoinjector being developed by Dr. Reddy's Laboratories; Imitrex(®) (Sumatriptan) injection 3 mg or 6 mg (6 mg/0.5 mL); or Imitrex STATdose 4 mg or 6 mg (0.5 mL). Blood was sampled for 12 hours to determine sumatriptan Cp. Maximum Cp (Cmax), area under the curve during the first 2 hours (AUC0-2), and total area under the curve (AUC0-∞) were determined using noncompartmental methods. Post hoc analyses were conducted to determine the relationship between these exposure metrics and each of body weight, BMI, age, sex, and race (categorized as white, black, or others). RESULTS: Both weight and BMI correlated negatively with each exposure metric for each treatment group. Across all treatment groups, AUC0-2 for subjects with BMI less than or equal to median value was 1.03-1.12 times the value for subjects with BMI more than median value. For subjects with BMI less than or equal to median value receiving DFN-11, median AUC0-2 was slightly less than that for subjects with BMI more than median value receiving Imitrex 4 mg and larger than that for subjects with BMI more than median value receiving Imitrex 3 mg. Results were similar for the other exposure metrics and for weight. Exposure was higher in women than in men, which can be attributed in part to differences in weight. There was no relationship between exposure and age. For DFN-11, AUC0-2 and AUC0-∞ were lower in nonwhites compared with whites; the ratio of median values was 0.84 and 0.89, respectively. A similar, nonstatistically significant, trend was observed in the other products (ratio of median values ranging from 0.84 to 0.89). CONCLUSION: Weight and BMI appear to be important covariates for sumatriptan exposure: subjects with lower values for either metric of body size have higher systemic exposure compared with subjects with higher values. Additional studies are required to determine if doses of subcutaneous sumatriptan may be adjusted based on BMI for comparable efficacy and a potentially improved tolerability profile.

Safety and pharmacokinetics of single and multiple intravenous bolus doses of diclofenac sodium compared with oral diclofenac potassium 50 mg: A randomized, parallel-group, single-center study in healthy subjects.

In a randomized, parallel-group, single-center study in 42 healthy adults, the safety and pharmacokinetic parameters of an intravenous formulation of 18.75 and 37.5 mg diclofenac sodium (DFP-08) following single- and multiple-dose bolus administration were compared with diclofenac potassium 50 mg oral tablets. Mean AUC0-inf values for a 50-mg oral tablet and an 18.75-mg intravenous formulation were similar (1308.9 [393.0]) vs 1232.4 [147.6]). As measured by the AUC, DFP-08 18.75 mg and 37.5 mg demonstrated dose proportionality for extent of exposure. One subject in each of the placebo and DFP-08 18.75-mg groups and 2 subjects in the DFP-08 37.5-mg group reported adverse events that were considered by the investigator to be related to the study drug. All were mild in intensity and did not require treatment. Two subjects in the placebo group and 1 subject in the DFP-08 18.75-mg group reported grade 1 thrombophlebitis; no subjects reported higher than grade 1 thrombophlebitis after receiving a single intravenous dose. The 18.75- and 37.5-mg doses of intravenous diclofenac (single and multiple) were well tolerated for 7 days. Additional efficacy and safety studies are required to fully characterize the product.

Long non-coding RNA MALAT1 regulates hyperglycaemia induced inflammatory process in the endothelial cells.

To examine whether the long non-coding RNA (lncRNA) metastasis associated lung adenocarcinoma transcript 1 (MALAT1) is altered in the endothelial cells in response to glucose and the significance of such alteration. We incubated human umbilical vein endothelial cells with media containing various glucose levels. We found an increase in MALAT1 expression peaking after 12 hrs of incubation in high glucose. This increase was associated with parallel increase in serum amyloid antigen 3 (SAA3), an inflammatory ligand and target of MALAT1 and was further accompanied by increase in mRNAs and proteins of inflammatory mediators, tumour necrosis factor alpha (TNF-α) and interleukin 6 (IL-6). Renal tissue from the diabetic animals showed similar changes. Such cellular alterations were prevented following MALAT1 specific siRNA transfection. Results of this study indicate that LncRNA MALAT1 regulates glucose-induced up-regulation of inflammatory mediators IL-6 and TNF-α through activation of SAA3. Identification of such novel mechanism may lead to the development of RNA-based therapeutics targeting MALAT1 for diabetes-induced micro and macro vascular complications.

Arterolane maleate plus piperaquine phosphate for treatment of uncomplicated Plasmodium falciparum malaria: a comparative, multicenter, randomized clinical trial.

BACKGROUND: Artemisinin-based combination therapy is the first-line treatment for uncomplicated falciparum malaria. This study assessed the antimalarial efficacy and safety of a combination of 150 mg of arterolane maleate and 750 mg of piperaquine phosphate (AM-PQP) in comparison to Coartem (artemether and lumefantrine) in patients with acute uncomplicated P. falciparum malaria. METHODS: In this open-label, randomized, multicentric, parallel group clinical trial, 240 patients were randomized to receive AM-PQP (160 patients) or Coartem (80 patients). Patients with P. falciparum monoinfection and initial parasite densities ranging from 1000 to 100 000 asexual parasites/µL of blood were followed for 28 days. Polymerase chain reaction-corrected adequate clinical and parasitologic response on day 28, parasite clearance time, and fever clearance time were evaluated. RESULTS: A total of 151 (94.4%) of 160 patients in the AM-PQP group completed the trial, while 77 (96.3%) of 80 patients in the Coartem group completed the trial. No treatment failure was noted in the AM-PQP group, while one patient receiving Coartem failed treatment on day 28. There was no difference in the median parasite clearance time (30 hours in both groups) or median fever clearance time (24 hours in both groups) after administration of the 2 study treatments. CONCLUSIONS: The available data support the evaluation of a drug combination in a larger population as a fixed-dose combination. Clinical Trials Registration. CTRI/2007/091/000031.

Pharmacokinetics and pharmacodynamics of arterolane maleate following multiple oral doses in adult patients with P. falciparum malaria.

Arterolane (RBx 11160) maleate is a novel, rapidly acting synthetic trioxolane antimalarial compound being developed by Ranbaxy Research Laboratories (Haryana, India). It is presently under phase III in combination with piperaquine phosphate. The present work reports the relationship between pharmacokinetic (PK) parameter (AUC(0-8h) on day 0/day 6) and indices of pharmacodynamic (PD) response (50% parasite clearance [PC(50)], 90% parasite clearance [PC(90)], parasite clearance time [PCT], recrudescence) from a phase II, double-blind, multicenter, randomized, parallel-group, dose-ranging trial. Patients with acute uncomplicated P. falciparum malaria were randomized to 1 of 3 arterolane maleate (50, 100, and 200 mg) doses for 7 consecutive days. Plasma concentration data were available from 78, 76, and 75 patients receiving a 50-, 100-, and 200-mg dose, respectively. Based on PD modeling, its limitations and assumptions, minimum 150-mg dose arterolane maleate was recommended to optimize the probability of maximum therapeutic benefits for an adult. Doses higher than 100 mg are unlikely to reduce the probability of recrudescence. This study re-stresses the need of combining short and long-acting drugs to prevent resistance development and minimize recrudescence.

Arterolane, a new synthetic trioxolane for treatment of uncomplicated Plasmodium falciparum malaria: a phase II, multicenter, randomized, dose-finding clinical trial.

BACKGROUND: Drug-resistant Plasmodium falciparum malaria necessitates development of novel drugs for treatment.The present study assessed the efficacy and safety of 3 dose levels of arterolane (RBx 11160), a synthetic trioxolane, for treatment of acute uncomplicated falciparum malaria. METHODS: In this randomized, double-blind, multicenter, parallel-group, dose-finding, phase II trial, 230 patients from 4 centers in Thailand, India, and Tanzania (mainland and Zanzibar) received either 50 mg (n=78), 100mg (n=76), or 200 mg (n=76) of arterolane once daily for 7 days. Patients (aged 13-65 years) with asexual parasite density of 1000-100,000 parasites/microL were included and were followed up for 28 days. The median time to 90% parasite clearance (PC90) was evaluated. RESULTS: The median PC90 was longer in the group receiving the 50-mg dose (19.4 h), compared with the groups receiving the 100-mg dose (12.8 h) and 200-mg dose (12.6 h) (P < .01). The polymerase chain reaction-corrected adequate clinical and parasitological responses on day 28 were 63%, 71%, and 72% for the groups receiving the 50-mg, 100-mg, and 200-mg doses, respectively, by intention-to-treat analysis (odds ratio, 1.55; 95%confidence interval, 0.78-3.06, for comparison of the 200-mg and 50-mg dose groups). Treatment was generally well tolerated. No patient died or experienced any serious adverse event. Mild complaints were reported in <10%of the patients and were similar in the 3 groups. Biochemistry and hematological analyses did not show any signof drug toxicity in any patient. CONCLUSION: Arterolane at daily doses of 100 and 200 mg is a rapidly acting, effective, and safe synthetic antimalarial drug, which may potentially represent an alternative to artemisinin derivatives in antimalarial combination therapy. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT00362050.

Pharmacokinetics and pharmacodynamics of endoperoxide antimalarials.

There are several clinically useful endoperoxides, mainly artemisinin derivatives available in market for the treatment of malaria. These are highly potent drugs, with fastest parasite reduction ratio, broadest parasite stage specificity and effectiveness against all species of plasmodium in human. Endoperoxides are crystalline compounds having poor aqueous solubility. Several theories have been proposed for their mechanism of action, but the understanding is still incomplete. The major limitation of this class of compounds is the short half-life, requiring frequent administration, leading to noncompliance and recrudescence. Therefore, WHO recommends their use in combination with long acting antimalarial drugs (Artemisinin based combination therapy, ACT) to manage drug resistance, recrudescence, and non compliance. Endoperoxide compounds bind selectively to malaria-infected red blood cells and moderately to human plasma proteins. Artemisinin derivatives are converted primarily to the bioactive metabolite dihydroartemisinin after parenteral, oral or rectal administration. The rate of conversion is lowest for artelinic acid and highest for the water-soluble artesunate. Such conversion occurs largely in the liver by CYP enzymes. Oral bioavailability in animals ranges between 19 to 35%. Based on their liphophilicity, they tend to cross the blood-brain barrier, causing neurotoxicity in animal models. Efforts have been made to understand and develop pharmacokinetic-pharmacodynamic (PK-PD) correlation and identify PK-PD indices of endoperoxides. In the absence of the above, the selection of doses in ACTs has been empirical. There are several reports on clinical pharmacokinetic interactions of endoperoxides and their long acting partner drugs but as on date no clinically significant interaction has been reported. This review is an update on physicochemical, pharmacokinetic and pharmacodynamic properties of the endoperoxide antimalarials.

Safety, tolerability, and single- and multiple-dose pharmacokinetics of piperaquine phosphate in healthy subjects.

Piperaquine phosphate is an orally active bisquinolone antimalarial drug that has been used for the past 3 decades. The authors report the safety, tolerability, and pharmacokinetics of piperaquine from a classical controlled phase I study. It was a double-blind, randomized, parallel-group, placebo-controlled, and single- and multiple-dose study. During the rising single-dose study, single ascending oral doses of 500, 750, 1000, 1250, and 1500 mg of piperaquine phosphate were administered, whereas in rising multiple-dose study, once-daily ascending oral doses of 500, 750, 1000, and 1500 mg were administered for 3 consecutive days. Pharmacokinetic analysis for both the rising single- and multiple-dose studies was done using the noncompartmental approach. The mean apparent terminal half-life ranged from 11 to 23 days. Increase in exposure was less than dose proportional and linear. Piperaquine concentrations were measurable up to 60 days postdose. Multiple peaks were observed in the plasma piperaquine concentration-time profiles and exhibited 3- to 7-fold accumulation following multiple dosing. Piperaquine was well tolerated following single and multiple doses.

Sensitive and rapid liquid chromatography/tandem mass spectrometric assay for the quantification of piperaquine in human plasma.

A simple, sensitive and rapid liquid chromatography/tandem mass spectrometric (LC-MS/MS) method was developed and validated for quantification of piperaquine, an antimalarial drug, in human plasma using its structural analogue, piperazine bis chloroquinoline as internal standard (IS). The method involved a simple protein precipitation with methanol followed by rapid isocratic elution of analytes with 10mM ammonium acetate buffer/methanol/formic acid/ammonia solution (25/75/0.2/0.15, v/v) on Chromolith SpeedROD RP-18e reversed phase chromatographic column and quantification by mass spectrometry in the multiple reaction monitoring mode (MRM). The precursor to product ion transitions of m/z 535.3-->288.2 and m/z 409.1-->205.2 were used to measure the analyte and the IS, respectively. The assay exhibited a linear dynamic range of 1.0-250.2 ng/mL for piperaquine in plasma. The limit of detection (LOD) and lower limit of quantification (LLOQ) in plasma were 0.2 and 1.0 ng/mL, respectively. Acceptable precision and accuracy (+/-20% deviation for LLOQ standard and +/-15% deviation for other standards from the respective nominal concentration) were obtained for concentrations over the standard curve ranges. A run time of 2.5 min for a sample made it possible to achieve a throughput of more than 400 plasma samples analyzed per day. The validated method was successfully applied to analyze human plasma samples from phase-1 clinical studies. The mean pharmacokinetic parameters of piperaquine following 1000 mg oral dose: observed maximum plasma concentration (Cmax), time to maximum plasma concentration (Tmax) and elimination half-life (T1/2) were 46.1 ng/mL, 3.8h and 13 days, respectively.