Simultaneous spectrophotometric estimation of tenofovir disoproxil fumarate and Lamivudine in three component tablet formulation containing efavirenz

Comparative application of derivative spectrophotometric and HPLC techniques for the simultaneous determination of lamivudine and tenofovir disoproxil fumarate in fixed-dose combined drugs

Background

Lamivudine (LAM) and tenofovir disoproxil fumarate (TDF) are part of a fixed-dose combination (FDC) therapy recommended by WHO. Both drugs exhibit similar solubility in many solvent systems and tend to have overlapping spectra with maxima at 260 and 270 nm, respectively, in the UV spectrum—thus making their spectrophotometric assay difficult in FDCs. A third-order derivative (D3, d3A/dλ3) spectrophotometric technique was applied to simultaneously evaluate TDF and LAM in FDC drugs, with amplitudes at 240 and 262.5 nm, respectively. Pharmacopoeia-recommended chromatographic method was also applied for comparative purpose.

Results

Method performance by the proposed D3 technique showed linearity for LAM and TDF from 2–10 µg mL−1 to 8–24 µg mL−1, respectively (R2 ≥ 0.998), while for HPLC method both drugs ranged from 0.25 to 5.0 µg mL−1 (R2 ≥ 0.999). The intercepts and slopes of the regression equations were ≤ 1.62 × 10−4 and ≤ 3.58 × 10−5, respectively, while calculated standard errors were ≤ 8.04 × 10−5. Limits of detection and quantification for both methods were ≤ 0.46 μg mL−1 and ≤ 1.40 μg mL−1, respectively, for LAM, while corresponding limits for TDF were ≤ 2.61 and ≤ 7.90 μg mL−1. The percentage recovery for both drugs and methods ranged from 94.80 to 100.33%. The amount of LAM and TDF in brands I and II was ≥ 99.59 ± 1.19% and ≥ 99.39 ± 0.63%, respectively, for the proposed D3 spectroscopic method, while corresponding values for the HPLC method were ≥ 99.86 ± 0.50 and ≥ 99.87 ± 0.32%. Statistically, both methods were adjudged to have no significant difference at 95% confidence level as the student’s t-test values; experimental paired t- and F-test values were found satisfactory.

Conclusion

The D3 spectrophotometric technique was time saving, cheap, simple and more environmental friendly and shows reliability, precision and accuracy and could be used for routine analysis of FDCs where HPLC is not available.

Graphical abstract

Anti-retroviral drugs induced photosensitivity may be two culprits in mixed formulation, a case report and literature review

Although the most frequent presentation of adverse drug events amongst HIV- infected individuals is skin rash, photosensitivity is uncommon. We herein described an HIV-infected female who presented with photo-distributed annular target-like eruptions and small tense blisters. Our patient had objectively reduced erythemal thresholds on broadband UV phototesting, to both UVA and UVB. Resolution of the abnormal responses on retesting undertaken after cessation of the tenofovir disoproxil fumarate and efavirenz in mixed formulation for five months confirmed a diagnosis of drug-induced photosensitivity. Given the preferred first-line anti-retroviral therapy which usually contains both TDF and EFV, photoprotection from broad-band ultraviolet wavelengths should be emphasized for the patients receiving this antiretroviral regimen.

Concurrent estimation of lamivudine, tenofovir disoproxil fumarate, and efavirenz in blended mixture and triple combination tablet formulation by a new stability indicating RP-HPLC method

Background

An easy, defined, rapid, and accurate reverse phase high-performance liquid chromatography method was developed and subsequently validated for the concurrent estimation of lamivudine, efavirenz, and tenofovir disoproxil fumarate in their pure blend and combined tablet formulation. An efficient and appropriate separation of the three analytes was attained with Zorbax eclipse XDB-Phenyl column, with a mobile phase of methanol: buffer (0.1% v/v formic acid in water) (73:27 v/v) at a flow rate of 1mL/min and isocratic elution by using 260nm as detection wavelength. Equal ratio of acetonitrile and water was used as diluent.

Results

The retention times of lamivudine, tenofovir disoproxil fumarate, and efavirenz were found at 2.6, 4.4, and 5.9 min respectively. The linear response for lamivudine, tenofovir disoproxil fumarate, and efavirenz was in the range of 15.0–45.0μg/mL, 15.0–45.0μg/mL, and 20.0–60.0 μg/mL respectively. The method validation was done in accordance to ICH guidelines and all validation parameters in compliance with ICH standards. The degradants produced by stress testing were well resolved from the peaks of active analytes, which stipulates the stability-indicating property of the method.

Conclusion

The method has the ability to separate lamivudine, efavirenz, and tenofovir disoproxil fumarate concurrently in blended powder and their combined tablet. All degradants produced by application of stress conditions were separated with high resolution and determined with good sensitivity that ensures the stability-indicating property of the method. Thus, the projected method has high probability to adopt in the pharmaceutical industrial sector.

A new stability indicating RP-UPLC method for simultaneous estimation of Doravirine, Lamivudine and Tenofovir disoproxil fumarate in bulk and their combined pharmaceutical formulation

Background

To establish a simple, sensitive, accurate, precise, efficient, economical RP-UPLC method for simultaneous estimation of Doravirine, Lamivudine and Tenofovir disoproxil fumarate in bulk and their combined pharmaceutical formulations. Optimization of Chromatographic separation was achieved on analytical column HSS C18 (100 × 2.1 mm, 1.8 μ) maintained at temperature 30 °C and mobile phase consisting of 0.01 N Potassium dihydrogen orthophosphate buffer (pH-4.8) and acetonitrile in the ratio 60:40 v/v and at a flow rate 0.3 mL/min in isocratic mode. The injection volume was set as 1 µl detection wavelength is 260 nm. The proposed method validation was done as per International Council on Harmonization Q2 (R1) guidelines.

Results

Doravirine, Lamivudine and Tenofovir disoproxil fumarate were eluted at retention times of 1.2, 1.5, and 1.8 min respectively. The proposed method was identified an excellent linearity over concentration range of 12.5–75.0 µg/mL for Doravirine and 37.5–225.0 µg/mL for Lamivudine and 37.5–225.0 µg/mL for Tenofovir disoproxil fumarate. The percentage relative standard deviation for intra-day and inter-day precision of the present method was less than 2% for Doravirine, Lamivudine and Tenofovir disoproxil fumarate. Accuracy of the present method was evaluated by recovery studies which were in the range of 99.62–99.88% for Doravirine and 98.78–99.44% for Lamivudine and 99.67–100.52% for Tenofovir disoproxil fumarate. The limit of detection and limit of quantification were found to be 0.249 µg/mL and 0.756 µg/mL for Doravirine and 0.24 µg/mL and 0.727 µg/mL for Lamivudine and 0.797 µg/mL and 2.966 µg/mL for Tenofovir disoproxil fumarate. Forced degradation studies were carried out under various stress conditions like acid, base, peroxide, thermal, photo and neutral conditions.

Conclusions

The present method makes sure about no degraded impurity peak interference at the retention time of analyte peak hence can be applied for quality control investigation of Doravirine, Lamivudine and Tenofovir disoproxil fumarate in bulk and pharmaceutical formulations.

A simple stability indicating RP-HPLC-DAD method for concurrent analysis of Tenofovir Disoproxil Fumarate, Doravirine and Lamivudine in pure blend and their combined film coated tablets

OBJECTIVES

The main aim of the study was to develop an economical, insightful, accurate and simple RP-HPLC-DAD method with high precision and good sensitivity for concurrent determination of Tenofovir disoproxil fumarate, Doravirine and Lamivudine in blended bulk form and their combined tablet form.

MATERIAL AND METHODS

A method with Ascentis C18 (150×4.6mm, 5μm) column, mobile phase ratio of 0.1% ortho phosphoric acid and Acetonitrile in 70:30 (v/v), 1mL/min flow rate and detection wavelength of 260nm was highly proficient in effective separation of all three drugs. The developed method was validated in accordance with ICH specifications.

RESULTS

The retention times of Doravirine, Lamivudine and Tenofovir disoproxil fumarate observed were 2.4, 2.9, and 3.6min, respectively. The linear responses were observed for Doravirine, Lamivudine and Tenofovir disoproxil fumarate in the range of 12.5-75μg/mL, 75-225μg/mL and 75-225μg/mL, respectively. The limit of detection and quantification values were calculated to be 0.36μg/mL and 0.11μg/mL for Lamivudine, 0.55μg/mL and 1.66μg/mL for Tenofovir disoproxil fumarate and 0.03μg/mL and 0.09μg/mL for Doravirine. The % RSD values of the intra-day and inter-day precision were calculated in the range of 0.134-1.749. The mean percentage recovery of all three analytes was in the range of 98.85-100.18%. The statistical results of the validation parameters ensured that the method was accurate, specific, and precise with good sensitivity. Investigation of analytes under different stressed conditions ensures the stability of analytes reflecting the stability indication of the method. The developed method has high proficiency in separation of Tenofovir disoproxil fumarate, Doravirine and Lamivudine. The degradation products generated due to stress conditions also separated with good resolution.

CONCLUSION

The current method is a stability-indicating assay method consisting of appropriate specificity, accuracy, precision and sensitivity. The developed method has a good potential to be adopted by the pharmaceutical industrial sector.

Forced Degradation Study for Tenofovir DF, Lamivudine and Efavirenz in Triple Combination Anti-Retroviral Tablets and Development of Validated Stability Indicating Assay Method by UPLC

Introduction:

Tenofovir Disoproxil Fumarate/Lamivudine/Efavirenz Tablets are a pharmaceutical dosage form indicated for the treatment of Human Immunodeficiency Virus (HIV) infection.

Methods:

A simple, time efficient and stability indicating Reverse Phase Ultra Performance Liquid Chromatography (RP – UPLC) method was developed for the simultaneous determination of the three drugs present in the tablets. Mobile phase-A is 0.1% Trifluoro Acetic acid in water and mobile phase-B is acetonitrile in gradient elution mode. Flow rate at 0.4 mL/min was fixed in the method. Acquity BEH Phenyl (100 mm × 2.1 mm), 1.7 µ column was used for the separation of analytes at 260 nm wavelength. The developed method has been validated as specified in International Conference on Harmonization (ICH) guideline. Forced degradation study was conducted for Tenofovir Disoproxil fumarate (TDF), Lamivudine (LAM) and Efavirenz (EFA) pharmaceutical tablets to identify the degradation behaviour of individual drugs under stress study.

Results:

The method was observed to be linear from 6-90 µg/mL concentration for TDF & LAM and 12-180 µg/mL for EFA with correlation coefficient values of more than 0.999. The method was found to be precise with RSD (Relative standard deviation) values of below 2% for replicate measurements. Recovery results were found to be between 99.0 and 100.8%. LOQ values for TDF, LAM & EFA were 0.041 µg/mL, 0.034 µg/mL & 0.053 µg/mL, respectively. Specificity of the analytical method was checked by injecting the stressed samples and evaluating the homogeneity of peaks using Photo Diode Array (PDA) detector. Peak purity results indicated that no interference was observed from degradation impurities for the quantification of TDF, LAM and EFA in the dosage form. The method was found to be robust under the deliberately modified chromatographic parameters.

Conclusion:

The developed UPLC method is stability indicating, successfully validated and suitable for quantification purpose.

Simultaneous Spectrophotometric Method for Determination of Emtricitabine and Tenofovir Disoproxil Fumarate in Three-Component Tablet Formulation Containing Rilpivirine Hydrochloride

Developing a single analytical method for estimation of individual drug from a multidrug composition is a very challenging task. A complexation, derivatization, extraction, evaporation, and sensitive-free direct UV spectrophotometric method is developed and validated for the simultaneous estimation of some antiviral drugs such as emtricitabine (EMT), tenofovir disoproxil fumarate (TDF), and rilpivirine HCl (RPV) in tablet dosage form by Vierordt's method. The solutions of standard and sample were prepared in methanol. The λ_max⁡ for emtricitabine, tenofovir disoproxil fumarate, and rilpivirine hydrochloride were 240.8 nm, 257.6 nm, and 305.6 nm, respectively. Calibration curves are linear in the concentration ranges 4–12 μg/ml for EMT, 6–18 μg/ml for TDF, and 0.5–1.5 μg/ml for RPV, respectively. Results of analysis of simultaneous equation method were analyzed and validated for various parameters according to ICH guidelines.

RP-HPLC method for simultaneous estimation of tenofovir disoproxil fumarate, lamivudine, and efavirenz in combined tablet dosage form

Background:

A simple, precise, accurate, and rapid reverse phase-high performance liquid chromatography (RP-HPLC) method with UV-Visible detector has been developed and subsequently validated for the simultaneous determination of tenofovir disoproxil fumarate (TDF), lamivudine (LAMI), and efavirenz (EFV) in their combined tablet dosage form.

Materials and Methods:

The separation was based on the use of a Kromasil C₁₈ analytical column (150 × 4.6 mm, i.d., 5 μm). The mobile phase consisted of a mixture of 70 volumes of methanol and 30 volumes of 10 mM phosphate buffer (pH 5.0). The separation was carried out at 40°C temperature with a flow rate of 1 ml/min.

Results:

Quantitation was achieved with UV detection at 254 nm, with linear calibration curves at concentration ranges of 1–6 μg/ml for TDF and LAMI and 2–12 μg/ml for EFV. The recoveries obtained were 99.46–101.36% for LAMI, 99.57–101.42% for TDF, and 99.96–100.87 for EFV.

Conclusion:

The method was validated according to International conference of harmonisation guidelines in terms of accuracy, precision, specificity, robustness, limits of detection and quantitation, and other aspects of analytical validation.