An adaptive phase II/III safety and efficacy randomized controlled trial of single day or three-day fixed-dose albendazole-ivermectin co-formulation versus albendazole for the treatment of Trichuris trichiura and other STH infections. ALIVE trial protocol.

Background: Soil-transmitted helminths (STH) are targeted for control through mass drug-administration campaigns to prevent morbidity affecting at-risk groups in endemic regions. Although broadly successful, the use of albendazole and mebendazole achieved variable progress, with deficiencies against Trichuris trichiura and a predictable low efficacy against Strongyloides stercoralis. Novel drug combinations offer a potential solution, providing they can be delivered safely and maintain efficacy against all STH species. Here we present the protocol of a clinical trial to evaluate a fixed-dose combination (FDC) tablet containing albendazole and ivermectin that will be compared against albendazole against STH . Methods: An adaptive phase II/III randomized controlled trial will be undertaken in STH endemic sites in Ethiopia, Kenya and Mozambique to evaluate an oral FDC of 400 mg albendazole and either 9- or 18 mg ivermectin. FDC will be administered as a single dose or single doses over three-consecutive days and assessed against a single dose of 400 mg albendazole. In the phase II trial, 126 T. trichiura-infected children weighting 15 to 45 kg will be treated in a dose-escalation manner to determine safety objectives. In the phase III trial, 1097 participants aged 5 to 18 years old infected with T. trichiura, hookworm and S. stercoralis will be recruited to determine safety and efficacy. The trial will be open-label with blinded outcome assessors. Cure rate measured 21-days after-treatment in duplicate Kato-Katz is the primary efficacy outcome. Secondary objectives include efficacy evaluation by quantitative polymerase chain reaction (PCR) as an outcome measurement, description of pharmacokinetic parameters, palatability and acceptability evaluations, and monitoring of anthelmintic resistance. Conclusions: This trial with registrational goals seeks to evaluate an innovative fixed-dose combination of albendazole and ivermectin co-formulated tablets, with the goal of providing an anthelmintic regimen with improved efficacy and spectrum of coverage against STH. ClinicalTrials.gov registration: NCT05124691 (18/11/2021).

The Kappa Opioid Receptor and the Sleep of Reason: Cortico-Subcortical Imbalance Following Salvinorin-A.

BACKGROUND: The mechanisms through which kappa opioid receptor (KOR) agonists induce psychotomimetic effects are largely unknown, although the modulation of this receptor has attracted attention for its clinical use. In this work, we characterize the neuropharmacological effects of salvinorin-A, a highly selective KOR agonist. METHODS: Changes in multimodal electroencephalography, single-photon emission computed tomography, and subjective effects following the acute administration of salvinorin-A are reported. The study included 2 sub-studies that employed a double-blind, crossover, randomized, placebo-controlled design. RESULTS: The electroencephalography measures showed a marked increase in delta and gamma waves and a decrease in alpha waves while subjects were under the effect of salvinorin-A. Regarding single-photon emission computed tomography measures, significant decreases in regional cerebral blood flow were detected in multiple regions of the frontal, temporal, parietal, and occipital cortices. Significant regional cerebral blood flow increases were observed in some regions of the medial temporal lobe, including the amygdala, the hippocampal gyrus, and the cerebellum. The pattern of subjective effects induced by salvinorin-A was similar to those observed in relation to other psychotomimetic drugs but with an evidently dissociative nature. No dysphoric effects were reported. CONCLUSION: The salvinorin-A-mediated KOR agonism induced dramatic psychotomimetic effects along with a generalized decrease in cerebral blood flow and electric activity within the cerebral cortex.

Safety and pharmacokinetic profile of fixed-dose ivermectin with an innovative 18mg tablet in healthy adult volunteers.

Ivermectin is a pivotal drug for the control of onchocerciasis and lymphatic filariasis, which is increasingly identified as a useful drug for the control of other Neglected Tropical Diseases. Its role in the treatment of soil transmitted helminthiasis through improved efficacy against Trichuris trichiura in combination with other anthelmintics might accelerate the progress towards breaking transmission. Ivermectin is a derivative of Avermectin B1, and consists of an 80:20 mixture of the equipotent homologous 22,23 dehydro B1a and B1b. Pharmacokinetic characteristics and safety profile of ivermectin allow to explore innovative uses to further expand its utilization through mass drug administration campaigns to improve coverage rates. We conducted a phase I clinical trial with 54 healthy adult volunteers who sequentially received 2 experimental treatments using a new 18 mg ivermectin tablet in a fixed-dose strategy of 18 and 36 mg single dose regimens, compared to the standard, weight based 150­200 µg/kg, regimen. Volunteers were recruited in 3 groups based on body weight. Plasma concentrations of ivermectin were measured through HPLC up to 168 hours post treatment. Safety data showed no significant differences between groups and no serious adverse events: headache was the most frequent adverse event in all treatment groups, none of them severe. Pharmacokinetic parameters showed a half-life between 81 and 91 h in the different treatment groups. When comparing the systemic bioavailability (AUC0t and Cmax) of the reference product (WA-ref) with the other two study groups using fixed doses, we observed an overall increase in AUC0t and Cmax for the two experimental treatments of 18 mg and 36 mg. Body mass index (BMI) and weight were associated with t1/2 and V/F, probably reflecting the high liposolubility of IVM with longer retention times proportional to the presence of more adipose tissue. Systemic exposure to ivermectin (AUC0t or Cmax) was not associated with BMI or weight in our study. These findings contribute to further understand the pharmacokinetic characteristics of ivermectin, highlighting its safety across different dosing regimens. They also correlate with known pharmacokinetic parameters showing stable levels of AUC and Cmax across a wide range of body weights, which justifies the strategy of fix dosing from a pharmacokinetic perspective. TRIAL REGISTRATION: ClinicalTrials.gov NCT03173742.

Naltrexone but Not Ketanserin Antagonizes the Subjective, Cardiovascular, and Neuroendocrine Effects of Salvinorin-A in Humans.

BACKGROUND: Salvinorin-A is a terpene found in the leaves of the plant Salvia divinorum. When administered to humans, salvinorin-A induces an intense but short-lasting modified state of awareness, sharing features with those induced by the classical serotonin-2A receptor agonist psychedelics. However, unlike substances such as psilocybin or mescaline, salvinorin-A shows agonist activity at the kappa-opioid receptor rather than at the serotonin-2A receptor. Here, we assessed the involvement of kappa-opioid receptor and serotonin-2A agonism in the subjective, cardiovascular, and neuroendocrine effects of salvinorin-A in humans. METHODS: We conducted a placebo-controlled, randomized, double-blind study with 2 groups of 12 healthy volunteers with experience with psychedelic drugs. There were 4 experimental sessions. In group 1, participants received the following treatment combinations: placebo+placebo, placebo+salvinorin-A, naltrexone+placebo, and naltrexone+salvinorin-A. Naltrexone, a nonspecific opioid receptor antagonist, was administered at a dose of 50mg orally. In group 2, participants received the treatment combinations: placebo+placebo, placebo+salvinorin-A, ketanserin+placebo, and ketanserin+salvinorin-A. Ketanserin, a selective serotonin-2A antagonist, was administered at a dose of 40mg orally. RESULTS: Inhalation of 1mg of vaporized salvinorin-A led to maximum plasma concentrations at 1 and 2 minutes after dosing. When administered alone, salvinorin-A severely reduced external sensory perception and induced intense visual and auditory modifications, increased systolic blood pressure, and cortisol and prolactin release. These effects were effectively blocked by naltrexone, but not by ketanserin. CONCLUSIONS: Results support kappa opioid receptor agonism as the mechanism of action underlying the subjective and physiological effects of salvinorin-A in humans and rule out the involvement of a serotonin-2A-mediated mechanism.

Controlled human malaria infection by intramuscular and direct venous inoculation of cryopreserved Plasmodium falciparum sporozoites in malaria-naïve volunteers: effect of injection volume and dose on infectivity rates.

BACKGROUND: Controlled human malaria infection (CHMI) by mosquito bite is a powerful tool for evaluation of vaccines and drugs against Plasmodium falciparum malaria. However, only a small number of research centres have the facilities required to perform such studies. CHMI by needle and syringe could help to accelerate the development of anti-malaria interventions by enabling centres worldwide to employ CHMI. METHODS: An open-label CHMI study was performed with aseptic, purified, cryopreserved P. falciparum sporozoites (PfSPZ Challenge) in 36 malaria naïve volunteers. In part A, the effect of the inoculation volume was assessed: 18 participants were injected intramuscularly (IM) with a dose of 2,500 PfSPZ divided into two injections of 10 µL (n = 6), 50 µL (n = 6) or 250 µL (n = 6), respectively. In part B, the injection volume that resulted in highest infectivity rates in part A (10 µL) was used to formulate IM doses of 25,000 PfSPZ (n = 6) and 75,000 PfSPZ (n = 6) divided into two 10-µL injections. Results from a parallel trial led to the decision to add a positive control group (n = 6), each volunteer receiving 3,200 PfSPZ in a single 500-µL injection by direct venous inoculation (DVI). RESULTS: Four/six participants in the 10-µL group, 1/6 in the 50-µL group and 2/6 in the 250-µL group developed parasitaemia. Geometric mean (GM) pre-patent periods were 13.9, 14.0 and 15.0 days, respectively. Six/six (100%) participants developed parasitaemia in the 25,000 and 75,000 PfSPZ IM and 3,200 PfSPZ DVI groups. GM pre-patent periods were 12.2, 11.4 and 11.4 days, respectively. Injection of PfSPZ Challenge was well tolerated and safe in all groups. CONCLUSIONS: IM injection of 75,000 PfSPZ and DVI injection of 3,200 PfSPZ resulted in infection rates and pre-patent periods comparable to the bite of five PfSPZ-infected mosquitoes. Remarkably, it required 23.4-fold more PfSPZ administered IM than DVI to achieve the same parasite kinetics. These results allow for translation of CHMI from research to routine use, and inoculation of PfSPZ by IM and DVI regimens. TRIAL REGISTRATION: ClinicalTrials.gov NCT01771848.

Randomized, open-label, blinded-endpoint, crossover, single-dose study to compare the pharmacodynamics of torasemide-PR 10 mg, torasemide-IR 10 mg, and furosemide-IR 40 mg, in patients with chronic heart failure.

PURPOSE: Diuretics are the primary treatment for the management of chronic heart failure (HF) symptoms and for the improvement of acute HF symptoms. The rate of delivery to the site of action has been suggested to affect diuretic pharmacodynamics. The main objective of this clinical trial was to explore whether a prolonged release tablet formulation of torasemide (torasemide-PR) was more natriuretically efficient in patients with chronic HF compared to immediate-release furosemide (furosemide-IR) after a single-dose administration. Moreover, the pharmacokinetics of torasemide-PR, furosemide-IR, and torasemide-IR were assessed in chronic HF patients as well as urine pharmacodynamics. METHODS: Randomized, open-label, blinded-endpoint, crossover, and single-dose Phase I clinical trial with three experimental periods. Torasemide-PR and furosemide-IR were administered as a single dose in a crossover fashion for the first two periods, and torasemide-IR 10 mg was administered for the third period. Blood and urine samples were collected at fixed timepoints. The primary endpoint was the natriuretic efficiency after administration of torasemide-PR and furosemide-IR, defined as the ratio between the average drug-induced natriuresis and the average drug recovered in urine over 24 hours. RESULTS: Ten patients were included and nine completed the study. Here, we present the results from nine patients. Torasemide-PR was more natriuretically efficient than furosemide-IR (0.096 ± 0.03 mmol/µg vs 0.015 ± 0.0007 mmol/µg; P < 0.0001). Mictional urgency was lower and more delayed with torasemide-PR than with furosemide-IR. CONCLUSION: In a study with a limited sample size, our results suggest that 10 mg of torasemide-PR is more natriuretically efficient than 40 mg of furosemide-IR after single-dose administration in patients with chronic HF over a 24-hour collection period. Further studies are necessary to evaluate potential pharmacodynamic differences between torasemide formulations and to assess its impact on clinical therapeutics.

Salvinorin-A Induces Intense Dissociative Effects, Blocking External Sensory Perception and Modulating Interoception and Sense of Body Ownership in Humans.

BACKGROUND: Salvinorin-A is a terpene with agonist properties at the kappa-opioid receptor, the binding site of endogenous dynorphins. Salvinorin-A is found in Salvia divinorum, a psychoactive plant traditionally used by the Mazatec people of Oaxaca, Mexico, for medicinal and spiritual purposes. Previous studies with the plant and salvinorin-A have reported psychedelic-like changes in perception, but also unusual changes in body awareness and detachment from external reality. Here we comprehensively studied the profiles of subjective effects of increasing doses of salvinorin-A in healthy volunteers, with a special emphasis on interoception. METHODS: A placebo and three increasing doses of vaporized salvinorin-A (0.25, 0.50, and 1mg) were administered to eight healthy volunteers with previous experience in the use of psychedelics. Drug effects were assessed using a battery of questionnaires that included, among others, the Hallucinogen Rating Scale, the Altered States of Consciousness, and a new instrument that evaluates different aspects of body awareness: the Multidimensional Assessment for Interoceptive Awareness. RESULTS: Salvinorin-A led to a disconnection from external reality, induced elaborate visions and auditory phenomena, and modified interoception. The lower doses increased somatic sensations, but the highest dose led to a sense of a complete loss of contact with the body. CONCLUSIONS: Salvinorin-A induced intense psychotropic effects characterized by a dose-dependent gating of external audio-visual information and an inverted-U dose-response effect on body awareness. These results suggest a prominent role for the kappa opioid receptor in the regulation of sensory perception, interoception, and the sense of body ownership in humans.

Direct venous inoculation of Plasmodium falciparum sporozoites for controlled human malaria infection: a dose-finding trial in two centres.

BACKGROUND: Controlled human malaria infection (CHMI) accelerates development of anti-malarial interventions. So far, CHMI is done by exposure of volunteers to bites of five mosquitoes carrying Plasmodium falciparum sporozoites (PfSPZ), a technique available in only a few centres worldwide. Mosquito-mediated CHMI is logistically complex, exact PfSPZ dosage is impossible and live mosquito-based interventions are not suitable for further clinical development. METHODS: An open-labelled, randomized, dose-finding study in 18-45 year old, healthy, malaria-naïve volunteers was performed to assess if intravenous (IV) injection of 50 to 3,200 aseptic, purified, cryopreserved PfSPZ is safe and achieves infection kinetics comparable to published data of mosquito-mediated CHMI. An independent study site verified the fully infectious dose using direct venous inoculation of PfSPZ. Parasite kinetics were assessed by thick blood smear microscopy and quantitative real time PCR. RESULTS: IV inoculation with 50, 200, 800, or 3,200 PfSPZ led to parasitaemia in 1/3, 1/3, 7/9, and 9/9 volunteers, respectively. The geometric mean pre-patent period (GMPPP) was 11.2 days (range 10.5-12.5) in the 3,200 PfSPZ IV group. Subsequently, six volunteers received 3,200 PfSPZ by direct venous inoculation at an independent investigational site. All six developed parasitaemia (GMPPP: 11.4 days, range: 10.4-12.3). Inoculation of PfSPZ was safe. Infection rate and pre-patent period depended on dose, and injection of 3,200 PfSPZ led to a GMPPP similar to CHMI with five PfSPZ-infected mosquitoes. The infectious dose of PfSPZ predicted dosage of radiation-attenuated PfSPZ required for successful vaccination. CONCLUSIONS: IV inoculation of PfSPZ is safe, well tolerated and highly reproducible. It shall further accelerate development of anti-malarial interventions through standardization and facilitation of CHMI. Beyond this, rational dose selection for whole PfSPZ-based immunization and complex study designs are now possible. TRIAL REGISTRATION: ClinicalTrials.gov NCT01624961 and NCT01771848 .

Pharmacodynamics assessment of Bemiparin after multiple prophylactic and single therapeutic doses in adult and elderly healthy volunteers and in subjects with varying degrees of renal impairment.

INTRODUCTION: Aging and renal impairment may prolong the half-life and lead to accumulation of low molecular weight heparins. Correct dosing is critical to prevent bleeding or thrombosis. MATERIALS AND METHODS: Open, parallel study. Healthy adult [n=13] and elderly (>65yrs) [n=12] volunteers; and subjects with mild (ClCr≥50 to ≤80mL/min, n=8), moderate (ClCr≥30 to <50mL/min, n=7), and severe (ClCr<30mL/min, n=8) renal impairment received four prophylactic doses (3,500IU/24h) and a single therapeutic dose (115IU/kg) of bemiparin with an interim washout period. Anti-FXa activity and the potential need for dose adjustment were evaluated. RESULTS: There were statistically significant differences in the severe renal impairment group vs. adult volunteers in all anti-FXa related parameters, but no significant differences in any of the anti-FXa related parameters between the adult and the elderly. Anti-FXa simulations after 10 prophylactic doses predicted mean Amax=0.59IU/mL in subjects with severe renal impairment and 0.33-0.39IU/mL in the rest. Simulations in the severe renal impairment group with dose adjustment (2,500IU/24h) predicted all individual Amax<0.60IU/mL (mean Amax=0.42IU/ml). Simulations after 10 therapeutic doses predicted mean Amax=1.22IU/mL in severe renal impairment group and 0.89-0.98IU/mL in the rest. Simulations in the severe renal impairment group with 75% dose adjustment predicted individual Amax≤1.60IU/mL (mean Amax=0.91IU/mL). CONCLUSIONS: No dose adjustments are required in elderly with preserved renal function. A dose adjustment of bemiparin is only advisable in patients with severe renal impairment when using prophylactic or therapeutic doses.

Psychomotor and subjective effects of bilastine, hydroxyzine, and cetirizine, in combination with alcohol: a randomized, double-blind, crossover, and positive-controlled and placebo-controlled Phase I clinical trials.

OBJECTIVE: The aim of this study was to compare the effects of concomitant administration of alcohol and bilastine versus alcohol alone on the central nervous system. METHODS: Twenty-four healthy young volunteers of both sexes participated in a randomized, double-blind, double-dummy, crossover, and positive-controlled and placebo-controlled clinical trials. At 1-week intervals, subjects received six different treatments: (i) placebo; (ii) alcohol 0.8 g/kg alone (ALC); (iii) ALC in combination with: bilastine 20 mg (B20 + A); (iv) bilastine 80 mg (B80 + A); (v) cetirizine 10 mg (CET + A); and (vi) hydroxyzine 25 mg (HYD + A). Psychomotor performance tests (fine motor, finger tapping, nystagmus, critical flicker-fusion frequency, temporal estimation, 'd2' cancellation, and simple reaction time) and subjective self-reports (drunkenness, drowsiness, mental slowness, clumsiness, anger, attentiveness, competence, happiness, hostility, interest, and extroversion) were carried out at baseline and multiple points thereafter. RESULTS: All active treatments induced a significant psychomotor impairment. The greatest and most lasting impairment was observed with HYD + A followed by B80 + A and CET + A. In contrast, objective measures showed less impairment with B20 + A and ALC, both with a similar magnitude. Self-reports showed a subjective perception of performance impairment in all active treatments. CONCLUSION: Concomitant administration of bilastine (at therapeutic dose) and alcohol does not produce greater central nervous system depressant effects than ACL alone.

Pharmacology of ayahuasca administered in two repeated doses.

RATIONALE: Ayahuasca is an Amazonian tea containing the natural psychedelic 5-HT(2A/2C/1A) agonist N,N-dimethyltryptamine (DMT). It is used in ceremonial contexts for its visionary properties. The human pharmacology of ayahuasca has been well characterized following its administration in single doses. OBJECTIVES: To evaluate the human pharmacology of ayahuasca in repeated doses and assess the potential occurrence of acute tolerance or sensitization. METHODS: In a double-blind, crossover, placebo-controlled clinical trial, nine experienced psychedelic drug users received PO the two following treatment combinations at least 1 week apart: (a) a lactose placebo and then, 4 h later, an ayahuasca dose; and (b) two ayahuasca doses 4 h apart. All ayahuasca doses were freeze-dried Amazonian-sourced tea encapsulated to a standardized 0.75 mg DMT/kg bodyweight. Subjective, neurophysiological, cardiovascular, autonomic, neuroendocrine, and cell immunity measures were obtained before and at regular time intervals until 12 h after first dose administration. RESULTS: DMT plasma concentrations, scores in subjective and neurophysiological variables, and serum prolactin and cortisol were significantly higher after two consecutive doses. When effects were standardized by plasma DMT concentrations, no differences were observed for subjective, neurophysiological, autonomic, or immunological effects. However, we observed a trend to reduced systolic blood pressure and heart rate, and a significant decrease for growth hormone (GH) after the second ayahuasca dose. CONCLUSIONS: Whereas there was no clear-cut tolerance or sensitization in the psychological sphere or most physiological variables, a trend to lower cardiovascular activation was observed, together with significant tolerance to GH secretion.

Rupatadine does not potentiate the CNS depressant effects of lorazepam: randomized, double-blind, crossover, repeated dose, placebo-controlled study.

AIM: The main objective was to assess whether benzodiazepine intake when rupatadine plasma concentrations were at steady-state would increase the CNS depressant effects. Rupatadine is a new H(1)-antihistamine which also inhibits platelet activating factor (PAF) release and has been shown to be clinically effective at doses of 10 mg. METHODS: Sixteen healthy young volunteers took part in a crossover, randomized, double-blind, placebo controlled trial comprising two experimental periods (repeated administration for 7 days of rupatadine 10 mg or placebo as single oral daily doses, separated by a washout of 14 days). On days 5 and 7, according to a fully balanced design, a single oral dose of lorazepam 2 mg or placebo was added. CNS effects were evaluated on these days by seven objective tests of psychomotor performance and eight subjective visual analogue scales (VAS) at pre-dose and several times after drug intake. Four treatment conditions were evaluated: placebo, rupatadine 10 mg, lorazepam 2 mg and rupatadine 10 mg + lorazepam 2 mg. RESULTS: Significant CNS effects, either impairment of psychomotor performance or subjective sedation, were observed when lorazepam was administered, either alone or in combination with steady state concentrations of rupatadine. No significant differences were found between these two conditions. In addition, rupatadine was not different from placebo. All treatments were well tolerated. CONCLUSION: Repeated doses of rupatadine (10 mg orally) did not enhance the CNS depressant effects of lorazepam (2 mg orally, single dose) either in objective psychomotor tasks or in subjective evaluations.