Challenges and opportunities in achieving bioequivalence for fixed-dose combination products

Amorphous Polymer-Phospholipid Solid Dispersions for the Co-Delivery of Curcumin and Piperine Prepared via Hot-Melt Extrusion

Curcumin and piperine are plant compounds known for their health-promoting properties, but their use in the prevention or treatment of various diseases is limited by their poor solubility. To overcome this drawback, the curcumin-piperine amorphous polymer-phospholipid dispersions were prepared by hot melt extrusion technology. X-ray powder diffraction indicated the formation of amorphous systems. Differential scanning calorimetry confirmed amorphization and provided information on the good miscibility of the active compound-polymer-phospholipid dispersions. Owing to Fourier-transform infrared spectroscopy, the intermolecular interactions in systems were investigated. In the biopharmaceutical properties assessment, the improvement in solubility as well as the maintenance of the supersaturation state were confirmed. Moreover, PAMPA models simulating the gastrointestinal tract and blood-brain barrier showed enhanced permeability of active compounds presented in dispersions compared to the crystalline form of individual compounds. The presented paper suggests that polymer-phospholipid dispersions advantageously impact the bioaccessibility of poorly soluble active compounds.

Bioequivalence of Elagolix/Estradiol/Norethindrone Acetate Fixed-Dose Combination Product: Phase 1 Results in Healthy Pre- and Postmenopausal Women

Fixed-dose combination (FDC) therapies can enhance patient convenience and adherence to prescribed treatment regimens. Elagolix is a novel oral gonadotropin-releasing hormone receptor antagonist approved for management of moderate to severe pain associated with endometriosis and heavy menstrual bleeding associated with uterine fibroids. Hormonal add-back therapy can attenuate the reversible hypoestrogenic effects of elagolix. An FDC formulation containing elagolix/estradiol (E2)/norethindrone acetate (NETA) 300/1/0.5 mg as the morning dose and an elagolix 300 mg capsule as the evening dose, were evaluated in 2 bioequivalence studies including the effects of food. Study 1 in premenopausal women assessed the bioavailability of the elagolix 300-mg capsule relative to the commercially available elagolix 300-mg tablet. Study 2 in postmenopausal women, elagolix/E2/NETA (300 mg/1 mg/0.5 mg) FDC capsule was assessed relative to the elagolix 300-mg tablet coadministered with E2/NETA 1-mg/0.5-mg tablet, the regimen that was studied in Phase 3 uterine fibroid studies. Under fasting conditions, the test elagolix 300-mg capsule was bioequivalent to the reference elagolix 300-mg tablet. Under fasting conditions, the elagolix/E2/NETA FDC capsule was bioequivalent to the coadministered elagolix 300-mg tablet and E2/NETA 1/0.5-mg tablet. Following administration of elagolix/E2/NETA FDC capsule after a high-fat breakfast, elagolix mean maximum concentration (Cmax) and area under the plasma concentration-time curve (AUC) were 38% and 28% lower, relative to fasting conditions. NETA mean Cmax was 51% lower and AUC from time 0 to infinity was 20% higher, while baseline-adjusted total estrone mean Cmax and AUC were 46% and 14% lower, respectively. No safety concerns were identified. These results enabled bridging the elagolix/E2/NETA FDC capsule.

Demonstrating Bioequivalence for Two Dose Strengths of Niraparib and Abiraterone Acetate Dual-Action Tablets Versus Single Agents: Utility of Clinical Study Data Supplemented with Modeling and Simulation

BACKGROUND AND OBJECTIVE

The combination of niraparib and abiraterone acetate (AA) plus prednisone is under investigation for the treatment of patients with metastatic castration-resistant prostate cancer (mCRPC) and metastatic castration-sensitive prostate cancer (mCSPC). Regular-strength (RS) and lower-strength (LS) dual-action tablets (DATs), comprising niraparib 100 mg/AA 500 mg and niraparib 50 mg/AA 500 mg, respectively, were developed to reduce pill burden and improve patient experience. A bioequivalence (BE)/bioavailability (BA) study was conducted under modified fasting conditions in patients with mCRPC to support approval of the DATs.

METHODS

This open-label randomized BA/BE study (NCT04577833) was conducted at 14 sites in the USA and Europe. The study had a sequential design, including a 21-day screening phase, a pharmacokinetic (PK) assessment phase comprising three periods [namely (1) single-dose with up to 1-week run-in, (2) daily dose on days 1-11, and (3) daily dose on days 12-22], an extension where both niraparib and AA as single-agent combination (SAC; reference) or AA alone was continued from day 23 until discontinuation, and a 30-day follow-up phase. Patients were randomly assigned in a parallel-group design (four-sequence randomization) to receive a single oral dose of niraparib 100 mg/AA 1000 mg as a LS-DAT or SAC in period 1, and patients continued as randomized into a two-way crossover design during periods 2 and 3 where they received niraparib 200 mg/AA 1000 mg once daily as a RS-DAT or SAC. The design was powered on the basis of crossover assessment of RS-DAT versus SAC. During repeated dosing (periods 2 and 3, and extension phase), all patients also received prednisone/prednisolone 5 mg twice daily. Plasma samples were collected for measurement of niraparib and abiraterone plasma concentrations. Statistical assessment of the RS-DAT and LS-DAT versus SAC was performed on log-transformed pharmacokinetic parameters data from periods 2 and 3 (crossover) and from period 1 (parallel), respectively. Additional paired analyses and model-based bioequivalence assessments were conducted to evaluate the similarity between the LS-DAT and SAC.

RESULTS

For the RS-DAT versus SAC, the 90% confidence intervals (CI) of geometric mean ratios (GMR) for maximum concentration at a steady state (Cmax,ss) and area under the plasma concentration-time curve from 0-24 h at a steady state (AUC 0-24h,ss) were respectively 99.18-106.12% and 97.91-104.31% for niraparib and 87.59-106.69 and 86.91-100.23% for abiraterone. For the LS-DAT vs SAC, the 90% CI of GMR for AUC0-72h of niraparib was 80.31-101.12% in primary analysis, the 90% CI of GMR for Cmax,ss and AUC 0-24h,ss of abiraterone was 85.41-118.34% and 86.51-121.64% respectively, and 96.4% of simulated LS-DAT versus SAC BE trials met the BE criteria for both niraparib and abiraterone.

CONCLUSIONS

The RS-DAT met BE criteria (range 80%-125%) versus SAC based on 90% CI of GMR for Cmax,ss and AUC 0-24h,ss. The LS-DAT was considered BE to SAC on the basis of the niraparib component meeting the BE criteria in the primary analysis for AUC 0-72h; abiraterone meeting the BE criteria in additional paired analyses based on Cmax,ss and AUC 0-24h,ss; and the percentage of simulated LS-DAT versus SAC BE trials meeting the BE criteria for both.

CLINICALTRIALS

GOV IDENTIFIER

NCT04577833.

Development and Characterization of Different Dosage Forms of Nifedipine/Indomethacin Fixed-Dose Combinations

Studies have shown that 40 individuals out of 100,000 are diagnosed with rheumatoid arthritis (RA) yearly, with a total of 1.3 million in the United States. Furthermore, the impact of RA in some cases can extend to cardiovascular diseases (CVD), as the studies showed that 84% of RA patients are at risk of developing hypertension. This study aims to design and develop different dosage forms (capsule-in-capsule and three-dimensional (3D) printed tablet) of nifedipine/indomethacin fixed-dose combination (FDC). The hot-melt extrusion (HME) was utilized alone and with fused deposition modeling (FDM) techniques The developed dosage forms were intended to provide delayed-extended and immediate release profiles for indomethacin and nifedipine, respectively. FDC dosage forms were successfully developed and characterized. Nifedipine formulations showed significant improvement in release profiles, having 94% of the drug release at 30 minutes compared with pure nifedipine, which had a percent release of 2%. Furthermore, the release of indomethacin was successfully delayed at a pH of 1.2 and extended at a pH of 6.8. Differential scanning calorimetry results showed endothermic crystalline peaks at 165 °C and 176 °C for indomethacin and nifedipine, respectively. Moreover, the thermal analysis of all formulations showed the absence of the endothermic peaks indicating complete solubilization of indomethacin and nifedipine in the polymeric carriers. All formulations had post-processing drug content in the range of 95% to 98%. Moreover, results from the stability study showed that all formulations were able to remain chemically and physically stable with no signs of recrystallization or degradation. The designed FDC dosage forms could improve the quality of life by enhancing patient compliance and preventing the need for polypharmacy.

Structure based design and evaluation of benzoheterocycle derivatives as potential dual HIV-1 protease and reverse transcriptase inhibitors

The development of dual inhibitors of HIV-1 protease and reverse transcriptase is an attractive strategy for multi-target therapeutic of AIDS, which may be privileged in delaying the occurrence of drug resistance. We herein designed a novel kind of dual inhibitors with benzofuran or indole cores. Biological results showed that a number of inhibitors displayed significant activity against both HIV-1 protease and reverse transcriptase. Among which, inhibitor 10f exhibited a good correlation with an approximate ratio of 1: 2 between the two enzymes. Furthermore, the dual inhibitors illustrated similar potency against both the wild-type virus and drug-resistant mutant. In addition, the molecular dynamic simulation studies verified the dual actions of such inhibitors.

A randomized, open-label, single-dose, two-way crossover study to assess the pharmacokinetics between two tablets of fixed-dose combination formulation with raloxifene and cholecalciferol and concomitant administration of each agents in healthy male volunteers

A new fixed-dose combination (FDC) formulation of raloxifene 60 mg and cholecalciferol 800 IU was developed to improve the medication compliance and overall efficacy of raloxifene treatment in postmenopausal osteoporosis patients. The aim of this study was to compare the pharmacokinetics between two tablets of FDC formulation of raloxifene/cholecalciferol and the two products administered concomitantly at respective doses. This randomized, open-label, single-dose, two-treatment, two-way crossover study included 46 volunteers. During each treatment period, subjects received the test formulation (FDC formulation containing raloxifene and cholecalciferol) or the reference formulation (co-administration of raloxifene and cholecalciferol), with a 14-d washout period. Serial blood samples were collected periodically over 96 hours after drug intake. In total, 46 subjects completed the study. The geometric mean ratios and its 90% confidence intervals of the FDC to the single agents for the area under the concentration-time curve from zero to the last quantifiable time point and the maximum plasma concentration met the regulatory criteria for bioequivalence: 1.1364 (1.0584–1.2201) and 1.1010 (0.9945–1.2188) for raloxifene and 1.0266 (0.9591–1.0989) and 1.0354 (0.9816–1.0921) for baseline-corrected cholecalciferol, respectively. Both formulations were well tolerated. No significant differences was observed in the incidence of adverse events between the two treatments. It was concluded that two tablets of the newly developed FDC formulation of raloxifene and cholecalciferol and the corresponding two agents administered concomitantly at respective doses were bioequivalent.

Cocrystal of Apixaban-Quercetin: Improving Solubility and Bioavailability of Drug Combination of Two Poorly Soluble Drugs

Drug combinations have been the hotspot of the pharmaceutical industry, but the promising applications are limited by the unmet solubility and low bioavailability. In this work, novel cocrystals, consisting of two antithrombotic drugs with poor solubility and low bioavailability in vivo, namely, apixaban (Apx) and quercetin (Que), were developed to discover a potential method to improve the poor solubility and internal absorption of the drug combination. Compared with Apx, the dissolution behavior of Apx–Que (1:1) and Apx–Que–2ACN (1:1:2) was enhanced significantly, while the physical mixture of the chemicals failed to exhibit the advantages. The dissolution improvements of Apx–Que–2ACN could be explained by the fact that the solid dispersion-like structure and column-shaped cage of Que accelerated the access of the solvent to the inner layer of Apx. The fracture of the hydrogen bonds of Apx, which was the joint of the adjacent Que chains, facilitated the break-up of the structures. Besides, the bioavailability of Apx–Que was increased compared with the physical mixture and Apx, and Apx–Que remained stable in high temperature and illumination conditions. Therefore, a drug–drug cocrystal of two antithrombotic agents with poor solubility was developed, which exhibited greatly improved solubility, bioavailability and superior stability, indicating a novel method to overcome the shortages of drug combination.

Insights into Dissolution and Solution Chemistry of Multidrug Formulations of Antihypertensive Drugs

Using fixed dose combinations of drugs instead of administering drugs separately can be beneficial for both patients and the health care system, but the current understanding of how multidrug formulations work at the molecular level is still in its infancy. Here, we explore dissolution, solubility, and supersaturation of various drug combinations in amorphous formulations. The effect of chemical structural similarity on combination behavior was investigated by using structurally related compounds of both drugs. The effect of polymer type on solution behavior was also evaluated using chemically diverse polymers. Indapamide (IPM) concentration decreased when combined with felodipine (FDN) or its analogues, which occurred even when the IPM solution was undersaturated. The extent of solubility decrease of FDN was less than that of IPM from the dissolution of an equimolar formulation of the drugs. No significant solubility decrease was observed for FDN at low contents of IPM which was also observed for other dihydropyridines, whereas FDN decreases at high contents of IPM. This was explained by the complex nature of the colloidal precipitates of the combinations which impacts the chemical potential of the drugs in solution at different levels. The maximum achievable concentration of FDN and IPM during dissolution of the polyvinylpyrrolidone-based amorphous solid dispersion was higher than the value measured with the hydroxypropyl methylcellulose acetate succinate-based formulation. This emphasizes the significance of molecular properties and chemical diversity of drugs and polymers on solution chemistry and solubility profiles. These findings may apply to drugs administered as a single dosage form or in separate dosage forms and hence need to be well controlled to assure effective treatments and patient safety.

Comparison of the Pharmacokinetics of a Fixed-Dose Combination of Rosuvastatin/Metformin Sustained-Release (10/1000 mg) and Separate Tablets in Healthy Male Subjects

Fixed-dose combination (FDC) drugs with various dose combinations for the treatment of type 2 diabetes mellitus and dyslipidemia are currently in demand. We compared the pharmacokinetic (PK) profiles of the rosuvastatin/metformin sustained-release (10/1000 mg) FDC and separate tablets and evaluated the effect of food by randomized, open-label, 3-period, 6-sequence crossover studies conducted in healthy male subjects. Subjects were randomly assigned to one of the following treatments: separate tablets of 10 mg rosuvastatin and 1000 mg metformin sustained release in the fed state and the FDC in the fasted and fed states. PK samples were collected up to 72 hours postdose for rosuvastatin, N-desmethyl rosuvastatin, and metformin. The PK parameters were determined using a noncompartmental method, and the geometric mean ratio (GMR) and the 90% confidence interval (CI) of the treatments were calculated. A total of 35 subjects completed the study. The GMR and 90%CI of the peak concentration (C_max ) and area under the plasma concentration-time curve from time zero to the last measurable concentration (AUC_last ) of the FDC and the separate tablets were within the bioequivalence criteria (0.8-1.25) for both rosuvastatin and metformin. The effect of food was statistically significant for both rosuvastatin and metformin but not expected to be of clinical significance.

Bioequivalence of Ertugliflozin/Sitagliptin Fixed-Dose Combination Tablets and Coadministration of Respective Strengths of Individual Components

A fixed-dose combination (FDC) tablet of ertugliflozin, a selective inhibitor of sodium-glucose cotransporter 2, and sitagliptin, a dipeptidyl peptidase-4 inhibitor, was developed for the treatment of patients with type 2 diabetes mellitus. Four studies were conducted under fasted conditions to demonstrate bioequivalence of ertugliflozin/sitagliptin FDC tablets and individual components at respective strengths when coadministered in healthy subjects. All studies had open-label, randomized, 2-period, 2-sequence, single-dose crossover designs. In each study 18 or 19 subjects were enrolled and received an ertugliflozin/sitagliptin FDC tablet (5 mg/50 mg, 5 mg/100 mg, 15 mg/50 mg, or 15 mg/100 mg) and corresponding strengths of ertugliflozin and sitagliptin coadministered as individual components. For both ertugliflozin and sitagliptin, the 90%CIs for the ratio (FDC:coadministration) of geometric means for area under the plasma concentration-time profile from time 0 extrapolated to infinite time, and maximum observed plasma concentration, were within acceptance criteria for bioequivalence (80% to 125%). All adverse events were mild in intensity. The 4 studies demonstrated that each strength of FDC tablet is bioequivalent to the respective dose of coadministered individual components. This indicates that the known efficacy and tolerability of ertugliflozin and sitagliptin when coadministered can be translated to the use of a FDC formulation.

"Development of Fixed Dose Combination Products" Workshop Report: Considerations of Gastrointestinal Physiology and Overall Development Strategy

The gastrointestinal (GI) tract is one of the most popular and used routes of drug product administration due to the convenience for better patient compliance and reduced costs to the patient compared to other routes. However, its complex nature poses a great challenge for formulation scientists when developing more complex dosage forms such as those combining two or more drugs. Fixed dose combination (FDC) products are two or more single active ingredients combined in a single dosage form. This formulation strategy represents a novel formulation which is as safe and effective compared to every mono-product separately. A complex drug product, to be dosed through a complex route, requires judicious considerations for formulation development. Additionally, it represents a challenge from a regulatory perspective at the time of demonstrating bioequivalence (BE) for generic versions of such drug products. This report gives the reader a summary of a 2-day short course that took place on the third and fourth of November at the Annual Association of Pharmaceutical Scientists (AAPS) meeting in 2018 at Washington, D.C. This manuscript will offer a comprehensive view of the most influential aspects of the GI physiology on the absorption of drugs and current techniques to help understand the fate of orally ingested drug products in the complex environment represented by the GI tract. Through case studies on FDC product development and regulatory issues, this manuscript will provide a great opportunity for readers to explore avenues for successfully developing FDC products and their generic versions.

Electrospun fixed dose formulations of amlodipine besylate and valsartan

Increasing numbers of elderly people require multi-drug therapies. One route to improve adherence rates is to prepare fixed dose combinations (FDCs), in which multiple active ingredients are loaded into a single formulation. Here, we report the use of electrospinning to prepare fast-dissolving oral FDCs containing amlodipine besylate and valsartan, two drugs prescribed as FDCs for the treatment of hypertension. Electrospun fibers were prepared loaded with one or both drugs, using polyvinylpyrrolidone as the polymer matrix. The fibers were largely cylindrical in morphology and comprise amorphous solid dispersions except with the highest loadings of amlodipine besylate. HPLC demonstrated drug entrapment efficiencies of >85% of the theoretical dose. The mats have folding endurances and thicknesses suitable for use as oral films. The amlodipine besylate-loaded systems are fast-dissolving, with >90% release obtained within 120 s. In contrast, valsartan release from its single-drug formulations took longer, ranging from 360 s to 24 min. With the FDC formulations, rapid release within 360 s was achieved when the loading was 5% w/w of each drug, but again the release time increased with drug loading. Electrospun fibers therefore have significant promise as FDCs, but the target drug and its loading need to be carefully considered.

Pharmacokinetic and bioequivalence study of a telmisartan/S-amlodipine fixed-dose combination (CKD-828) formulation and coadministered telmisartan and S-amlodipine in healthy subjects

Purpose

A new fixed-dose combination (FDC) formulation of telmisartan 80 mg and S-amlodipine 5 mg (CKD-828) has been developed to increase convenience (as only one tablet is required per day) and improve treatment compliance.

Methods

The pharmacokinetic characteristics and tolerability of an FDC of telmisartan and S-amlodipine were compared to those after coadministration of the individual agents in this randomized, open-label, single-dose, two-way, four-period, crossover study. To analyze the telmisartan and S-amlodipine plasma concentrations using a validated liquid chromatography–tandem mass spectrometry method, serial blood samples were collected up to 48 hours post-dose for telmisartan and 144 hours post-dose for S-amlodipine, in each period.

Results

Forty-eight healthy subjects were enrolled, and 43 completed the study. The mean peak plasma concentration (C_max) and the area under the plasma concentration–time curve from time 0 to the last measurement (AUC_0–t) values of telmisartan were 522.29 ng/mL and 2,475.16 ng·h/mL for the FDC, and 540.45 ng/mL and 2,559.57 ng·h/mL for the individual agents concomitantly administered, respectively. The mean C_max and AUC_0–t values of S-amlodipine were 2.71 ng/mL and 130.69 ng·h/mL for the FDC, and 2.74 ng/mL and 129.81 ng·h/mL for the individual agents concomitantly administered, respectively. The geometric mean ratio (GMR) and 90% confidence interval (CI) for the telmisartan C_max and AUC_0–t (FDC of telmisartan and S-amlodipine/concomitant administration) were 0.8509 (0.7353–0.9846) and 0.9431 (0.8698–1.0226), respectively. The GMR and 90% CI for the S-amlodipine C_max and AUC_0–t (FDC/concomitant administration) were 0.9829 (0.9143–1.0567) and 0.9632 (0.8798–1.0546), respectively. As the intrasubject variability of the C_max for telmisartan administered individually was 42.94%, all 90% CIs of the GMRs fell within the predetermined acceptance range. Both treatments were well tolerated in this study.

Conclusion

CKD-828 FDC tablets were shown to be bioequivalent to coadministration of the individual agents with the respective strength, in healthy subjects under fasting conditions. There was no significant difference in safety profile between the two treatments.

Patient-centered drug delivery and its potential applications for unmet medical needs

Pharmaceutical dosage forms address diverse key components but satisfying unmet patient needs to enhance patient adherence is a major challenge. The desired design of patient-centered drug products should be based on characteristics of various components, such as patients, disease, routes of administration, drug delivery technologies and active pharmaceutical ingredients. Understanding of targeting patients and their physiological and biological environments is pivotal for developing suitable patient-centered drug products. In this review, key components of an ideal drug delivery system were considered. Then, stepwise approaches for designing patient-centered drug products were suggested. Finally, various case studies are also presented and considered to develop models of patient-centered drug products.

Challenges for the pharmaceutical technical development of protein coformulations

Objectives

This review discusses challenges to stability, analytics and manufacturing of protein coformulations. Furthermore, general considerations to be taken into account for the pharmaceutical development of coformulated protein drug products are highlighted.

Key findings

Coformulation of two or more active substances in one single dosage form has recently seen increasing use offering several advantages, such as increased efficacy and/or the overall reduction of adverse event incidents in patients. Most marketed coformulated drug products are composed of small molecules. As proteins are not only comparatively large but also complex molecules, the maintenance of their physicochemical integrity within a formulation throughout pharmaceutical processing, storage, transport, handling and patient administration to ensure proper pharmacokinetics and pharmacodynamics in vivo already represents various challenges for single-entity products. Thus, nowadays, only sparse biologics-based coformulations can be found, as additional complexity during development is given for these products.

Summary

The complexity of the dosage form and the protein molecules results into additional challenges to formulation, manufacture, storage, transport, handling and patient administration, stability and analytics during the pharmaceutical development of protein coformulations. Various points have to be considered during different stages of development in order to obtain a safe and efficacious product.

Potential and development of inhaled RNAi therapeutics for the treatment of pulmonary tuberculosis

Tuberculosis (TB), caused by the infection of Mycobacterium tuberculosis (Mtb), continues to pose a serious threat to public health, and the situation is worsening with the rapid emergence of multidrug resistant (MDR) TB. Current TB regimens require long duration of treatment, and their toxic side effects often lead to poor adherence and low success rates. There is an urgent need for shorter and more effective treatment for TB. In recent years, RNA interference (RNAi) has become a powerful tool for studying gene function by silencing the target genes. The survival of Mtb in host macrophages involves the attenuation of the antimicrobial responses mounted by the host cells. RNAi technology has helped to improve our understanding of how these bacilli interferes with the bactericidal effect and host immunity during TB infection. It has been suggested that the host-directed intervention by modulation of host pathways can be employed as a novel and effective therapy against TB. This therapeutic approach could be achieved by RNAi, which holds enormous potential beyond a laboratory to the clinic. RNAi therapy targeting TB is being investigated for enhancing host antibacterial capacity or improving drug efficacy on drug resistance strains while minimizing the associated adverse effects. One of the key challenges of RNAi therapeutics arises from the delivery of the RNAi molecules into the target cells, and inhalation could serve as a direct administration route for the treatment of pulmonary TB in a non-invasive manner. However, there are still major obstacles that need to be overcome. This review focuses on the RNAi candidates that are currently explored for the treatment of TB and discusses the major barriers of pulmonary RNAi delivery. From this, we hope to stimulate further studies of local RNAi therapeutics for pulmonary TB treatment.

Bioequivalence of saxagliptin/dapagliflozin fixed-dose combination tablets compared with coadministration of the individual tablets to healthy subjects

Saxagliptin and dapagliflozin are individually indicated as an adjunct to diet and exercise to improve glycemic control in adults with type 2 diabetes mellitus. The bioequivalence of saxagliptin/dapagliflozin 2.5/5 mg and 5/10 mg fixed-dose combination (FDC) tablets compared with coadministration of the individual tablets and the food effect on both strengths of saxagliptin/dapagliflozin FDCs were evaluated in this open-label, randomized, single-dose crossover study. Healthy subjects were randomized to saxagliptin 2.5 mg + dapagliflozin 5 mg fasted, 2.5/5 mg FDC fasted, 2.5/5 mg FDC fed (Cohort 1) or saxagliptin 5 mg + dapagliflozin 10 mg fasted, 5/10 mg FDC fasted, 5/10 mg FDC fed (Cohort 2). Serial blood samples for pharmacokinetics of saxagliptin and dapagliflozin were obtained predose and up to 60 h postdose. Bioequivalence of FDC tablets versus individual components was concluded if the 90% CIs for FDC to individual component geometric mean ratios of C max, AUC 0-T, and AUC inf of both analytes were between 0.80 and 1.25. Seventy-two subjects were randomized; 71 (98.6%) completed the study. Saxagliptin/dapagliflozin 2.5/5 mg and 5/10 mg FDC tablets were bioequivalent to the individual tablets administered concomitantly. Food had no clinically meaningful effect on saxagliptin or dapagliflozin overall systemic exposure. Saxagliptin/dapagliflozin FDC tablets were bioequivalent to coadministration of the individual components in healthy subjects under fasted conditions and food had no clinically meaningful effect on bioavailability.

Rationale and clinical utility of the darunavir-cobicistat combination in the treatment of HIV/AIDS

This article is to provide an update overview of cobicistat (COBI)-boosted darunavir in response to its recent approval by the US Food and Drug Administration, and inclusion as an alternative first-line regime in the 2015 treatment guidelines in the US. COBI is a relatively new non-antiretroviral cytochrome P450 3A inhibitor or pharmacoenhancer. The rationale behind COBI development was to provide an alternative to ritonavir (RTV) as a protease inhibitor pharmacoenhancer, due to associated adverse events with short- and long-term RTV use, such as gastrointestinal intolerability, drug–drug interactions, insulin resistance, lipodystrophy, and hyperlipidemia. Although in vitro studies suggest that COBI may result in a lower incidence of undesired drug–drug interactions and lipid-associated disorders than RTV, not all Phase III studies have well addressed these issues, and the data are limited. However, Phase III studies have demonstrated tolerability, noninferiority, and bioequivalence of COBI compared to RTV. Two main advantages of COBI over RTV-containing regimes have been noted as follows: 1) COBI has no anti-HIV activity; therefore, resistance to COBI as a booster in addition to protease inhibitor resistance is of little concern, allowing for COBI-containing regimes in future. 2) COBI’s solubility and dissolution rate allow for co-formulated/fixed-dose combination products. Nonetheless, prior to initiating COBI-containing treatment regimens, the following should be considered: 1) COBI may increase serum creatinine levels and reduce estimated glomerular filtration rate (GFR) without affecting actual GFR; 2) potential drug–drug interaction data are insufficient, warranting caution when initiating COBI in conjunction with concomitant medication or in individuals with multiple comorbidities; 3) food plays a pivotal role in boosting darunavir exposure, warranting caution and patient education on the importance of taking COBI-containing regimens with appropriate amounts of food; and 4) data on the success of COBI-containing regimens in treatment-experienced patients are limited.