Implementation and Outcomes of a Pilot Collaborative Surgical Hydrocele Training in Côte d'Ivoire

Lymphatic filariasis (LF) is a neglected tropical disease that can cause hydrocele and its associated stigma, loss of economic productivity, and depression. Hydrocele surgery is an essential part of LF morbidity management but can be difficult for national programs to implement. To improve access to hydrocele surgeries in Côte d'Ivoire, we provided a WHO-certified surgical training for six surgical teams from five health districts in Côte d'Ivoire. We then evaluated the surgical outcomes and assessed the impact of hydrocele surgery on quality of life of hydrocelectomy patients. Preoperative and operative records were reviewed to describe baseline hydrocele characteristics and operative details. Postoperative interviews were conducted 4 to 6 months after surgical correction using a standardized questionnaire. Seventeen men underwent surgery during the training and were available for an interview at the 6-month visit. At the time of 6-month follow-up, 11/17 (64.7%) reported improvement in activities of daily living and reduction in difficulties with work, 8/17 (47.1%) reported an improved economic situation, 15/17 (88.2%) reported improved social interactions, and 15/16 (93.8%) reported improved sex life after surgical correction. Three patients (17.6%) had minor postoperative complications, but none required hospitalization. All 17 patients who were available for an interview were satisfied with their surgery. Surgical hydrocelectomy training in Côte d'Ivoire was well received and provided life-altering health improvements for participating patients across multiple domains of life. Support to scale up surgical capacity for this neglected problem is needed.

Safety and tolerability of moxidectin and ivermectin combination treatments for lymphatic filariasis in Côte d'Ivoire: A randomized controlled superiority study

BACKGROUND

Moxidectin is a macrocyclic lactone registered for the treatment of human onchocerciasis. The drug has a good safety profile, large volume of distribution and a long elimination half-life. This paper reports tolerability data from the first use of moxidectin in persons with Wuchereria bancrofti infection.

METHODS

In this randomized, open-label, masked-observer superiority trial, adults with Wuchereria bancrofti microfilaremia in Côte d'Ivoire were randomized to 1 of 4 treatment arms: ivermectin + albendazole (IA), moxidectin + albendazole (MoxA), ivermectin + diethylcarbamazine (DEC) + albendazole (IDA), or moxidectin + DEC + albendazole (MoxDA). As part of a larger efficacy trial, all participants were closely monitored for 7 days after treatment.

RESULTS

One hundred sixty-four individuals were treated, and monitored for treatment emergent adverse events (TEAE). Eighty-seven participants (53%) experienced one or more mild (grade 1) or moderate (grade 2) TEAE. Four participants had transient Grade 3 hematuria after treatment (3 after IDA and 1 after IA). There were no serious adverse events. There were no significant differences in frequency or types of TEAE between treatment groups (IA = 22/41 (53%), MoxA = 24/40 (60%), IDA = 18/41 (44%), MoxDA = 15/42 (36%), p = 0.530). Fifty-nine participants (36%) had multiple TEAE, and 8.5% had a one or more grade 2 (moderate) TEAE. Grade 2 TEAE were more frequent after triple drug treatments (IDA, 14.6%; MoxDA, 9.5%) than after two-drug treatments (IA, 7.3%; MoxA, 2.5%). There was no difference in TEAEs based on baseline Mf counts (OR 0.69 (0.33, 1.43), p-value 0.319).

CONCLUSION

All treatment regimens were well tolerated. We observed no difference in safety parameters between regimens that contained ivermectin or moxidectin.

TRIAL REGISTRATION

Clinicaltrials.gov, NCT04410406.

Population pharmacokinetic model of ivermectin in mass drug administration against lymphatic filariasis

BACKGROUND

Ivermectin (IVM) is a broad-spectrum anthelmintic drug used to treat diseases caused by filarial worms, such as onchocerciasis and lymphatic filariasis (LF). IVM is part of a triple-drug therapy used by the Mass Drug Administration (MDA) as a preventive strategy to eradicate LF in sub-Saharan Africa. The drug shows high variability in drug exposure in previous pharmacokinetic studies. This study aims to build a population pharmacokinetic (PopPK) model to identify and quantify the possible sources of the variability of IVM exposure after a single-oral dose in LF-infected subjects and healthy individuals.

METHODOLOGY / PRINCIPAL FINDINGS

In this analysis, 724 samples were collected from treatment-naïve Wuchereria bancrofti-infected (n = 32) and uninfected (n = 24) adults living in Côte d'Ivoire who had received one dose of IVM as a part of triple-drug therapy. PopPK analysis was conducted using Phoenix NLME 8.3 software. The Monte Carlo simulation based on the final model was performed to simulate drug exposure among different dosing groups (200 μg/kg, 18 mg, and 36 mg). A two-compartment model with zero-order dose input into the absorption compartment with a lag time function followed by first-order absorption and linear elimination best described the IVM's pharmacokinetic (PK) parameters. The final model identifies that the PK parameters of IVM are not affected by LF infection. Sex was a significant covariate on the peripheral volume of distribution (Vp/F, 53% lower in men than in women). IVM drug exposure shows linear pharmacokinetic behavior among the simulated dosing groups with similar drug exposure based on sex.

CONCLUSION/SIGNIFICANCE

We have developed a PopPk model to describe and identify possible sources of the variability of IVM exposure. To our knowledge, this is the first PopPK study of IVM in patients with LF.

TRIAL REGISTRATION

NCT02845713; NCT03664063.

Mass drug administration of ivermectin, diethylcarbamazine, plus albendazole compared with diethylcarbamazine plus albendazole for reduction of lymphatic filariasis endemicity in Papua New Guinea: a cluster-randomised trial

Background

Methods

Findings

Interpretation

Funding

A simple, high-throughput and validated LC-MS/MS method for determination of azithromycin in human plasma and its application to a clinical pharmacokinetic study

A sensitive, specific and rapid liquid chromatographic-tandem mass spectrometric (LC-MS/MS) method was developed and validated to quantify azithromycin concentrations in human plasma. Azithromycin (AZI) is the most common outpatient prescribed antibiotic in the US and clinical studies have demonstrated the efficacy and safety of AZI in many bacterial infections. To support a clinical study, we developed a high throughput LC-MS/MS method to process up to 250 samples per day to quantify AZI in human plasma. Samples were prepared by solid phase extraction. Separation was achieved with an ACE C₁₈ column (2.1 x 100 mm, 1.7 μm) equipped with a C₁₈ guard column. The mobile phase consisted of 0.1% formic acid and methanol/acetonitrile (1:1, v/v) at a flow rate of 0.25 mL/min. The ionization was optimized with positive electrospray source using multiple reaction monitoring transition, m/z 749.50>591.45 for AZI and m/z 754.50>596.45 for AZI-d5. Extraction recoveries were approximately 90% for AZI. The assay was linear from 0.5 to 2000 ng/mL and required only 100 μL of plasma with total analysis time of 4.5 minutes. The method was successfully applied to pharmacokinetic studies of a weight-based dosing protocol for AZI.

Efficacy and Safety of a Single Dose of Ivermectin, Diethylcarbamazine, and Albendazole for Treatment of Lymphatic Filariasis in Côte d'Ivoire: An Open-label Randomized Controlled Trial

Background

Improved drug regimens are needed to accelerate elimination of lymphatic filariasis in Africa. This study determined whether a single co-administered dose of ivermectin plus diethylcarbamazine plus albendazole [IDA] is noninferior to standard 3 annual doses of ivermectin plus albendazole (IA) used in many LF-endemic areas of Africa.

Methods

Treatment-naive adults with Wuchereria bancrofti microfilaremia in Côte d’Ivoire were randomized to receive a single dose of IDA (n = 43) or 3 annual doses of IA (n = 52) in an open-label, single-blinded trial. The primary endpoint was the proportion of participants who were microfilaria (Mf) negative at 36 months. Secondary endpoints were Mf clearance at 6, 12, and 24 months; inactivation of adult worm nests; and safety.

Results

At 36 months posttreatment with IDA, 18/33 (55%; 95% CI, 38–72%) cleared Mf versus 33/42 (79%; 67–91%) with IA (P = .045). At 6 and 12 months IDA was superior to IA in clearing Mf (89% [77–99%] and 71% [56–85%]), respectively, versus 34% (20–48%) and 26% (14–42%) (P < .001). IDA was equivalent to IA at 24 months (61% [45–77%] vs 54% [38–72%]; P = .53). IDA was superior to IA for inactivating adult worms at all time points. Both treatments were well tolerated, and there were no serious adverse events.

Conclusions

A single dose of IDA was superior to 2 doses of IA in reducing the overall Mf burden by 24 months. Reinfection may have contributed to the lack of sustained clearance of Mf with IDA.

Clinical Trials Registration

NCT02974049.

Semiannual Treatment of Albendazole Alone is Efficacious for Treatment of Lymphatic Filariasis: A Randomized Open-label Trial in Cote d'Ivoire

BACKGROUND

Ivermectin (IVM) plus albendazole (ALB), or IA, is widely used in mass drug administration (MDA) programs that aim to eliminate lymphatic filariasis (LF) in Africa. However, IVM can cause severe adverse events in persons with heavy Loa loa infections that are common in Central Africa. ALB is safe in loiasis, but more information is needed on its efficacy for LF. This study compared the efficacy and safety of three years of semiannual treatment with ALB to annual IA in persons with bancroftian filariasis.

METHODS

Adults with Wuchereria bancrofti microfilaremia (Mf) were randomized to receive either three annual doses of IA (N=52), six semiannual doses of ALB 400mg (N=45), or six semiannual doses of ALB 800mg (N=47). The primary outcome amicrofilaremia at 36 months.

FINDINGS

IA was more effective for completely clearing Mf than ALB 400mg or ALB 800mg (79%, CI 67-91; vs. 48%, CI 32-66 and 57%, CI 41-73, respectively). Mean % reductions in Mf counts at 36 months relative to baseline tended to be greater after IA (98%, CI 88-100) than after ALB 400mg (88%, CI 78-98) and ALB 800mg (89%, CI 79-99) (P=0.07 and P=0.06, respectively). Adult worm nest numbers (assessed by ultrasound) were reduced in all treatment groups. Treatments were well tolerated.

INTERPRETATION

Repeated semiannual treatment with ALB is macrofilaricidal for W. bancrofti and leads to sustained reductions in Mf counts. This is a safe and effective regimen that could be used as MDA to eliminate LF in areas ivermectin cannot be used.

Pharmacokinetics, safety, and efficacy of a single co-administered dose of diethylcarbamazine, albendazole and ivermectin in adults with and without Wuchereria bancrofti infection in Côte d'Ivoire

Background

A single co-administered dose of ivermectin (IVM) plus diethylcarbamazine (DEC) plus albendazole (ALB), or triple-drug therapy, was recently found to be more effective for clearing microfilariae (Mf) than standard DEC plus ALB currently used for mass drug administration programs for lymphatic filariasis (LF) outside of sub-Saharan Africa. Triple-drug therapy has not been previously tested in LF-uninfected individuals from Africa. This study evaluated the pharmacokinetics (PK), safety, and efficacy of triple-drug therapy in people with and without Wuchereria bancrofti infection in West Africa.

Methods

In this open-label cohort study, treatment-naïve microfilaremic (>50 mf/mL, n = 32) and uninfected (circulating filarial antigen negative, n = 24) adults residing in Agboville district, Côte d’Ivoire, were treated with a single dose of IVM plus DEC plus ALB, and evaluated for adverse events (AEs) until 7 days post treatment. Drug levels were assessed by liquid chromatography and mass spectrometry. Persons responsible for assessing AEs were blinded to participants’ infection status.

Findings

There was no difference in AUC_0-inf or C_max between LF-infected and uninfected participants (P>0.05 for all comparisons). All subjects experienced mild AEs; 28% and 25% of infected and uninfected participants experienced grade 2 AEs, respectively. There were no severe or serious adverse events. Only fever (16 of 32 versus 4 of 24, P<0.001) and scrotal pain/swelling in males (6 of 20 versus 0 of 12, P = 0.025) were more frequent in infected than uninfected participants. All LF positive participants were amicrofilaremic at 7 days post-treatment and 27 of 31 (87%) remained amicrofilaremic 12 months after treatment.

Conclusions

Moderate to heavy W. bancrofti infection did not affect PK parameters for IVM, DEC or ALB following a single co-administered dose of these drugs compared to uninfected individuals. The drugs were well tolerated. This study confirmed the efficacy of the triple-drug therapy for clearing W. bancrofti Mf and has added important information to support the use of this regimen in LF elimination programs in areas of Africa without co-endemic onchocerciasis or loiasis.

Trial registration

ClinicalTrials.gov NCT02845713.

Lymphatic filariasis is a mosquito-borne infection that causes disability in the form of lymphedema, hydroceles, and elephantiasis. It has been targeted for global elimination based on mass drug administration in the total population at risk including many people uninfected with LF. Recently, a single co-administered dose of IVM + DEC + ALB has been shown to be much more effective than the standard treatment with DEC + ALB for sustained clearance of Mf for 3 years based on studies in Papua New Guinea. This study confirms the efficacy and safety of triple-drug therapy for clearing of Wuchereria bancrofti Mf in an African population. The presence of LF did not affect drug levels and the medicines were well tolerated, with 28% and 25% rate of moderate AEs in infected and uninfected individuals respectively, and no severe or serious AEs, supporting the use of triple-drug therapy for mass drug administration. This study shows for the first time that triple-drug therapy also has a potent macrofilaricidal effect, as determined by the reduction in circulating filarial antigen and inactivation of worm nests one year following treatment.