Introduction: Doxorubicin is an anthracycline antibiotic used as an anticancer agent. Long-term use of this anticancer agent could accumulate its metabolite, doxorubicinol, and cause cardiomyopathy, due to its cardiotoxicity. This cardiotoxic effect depends on the amount of doxorubicin and doxorubicinol accumulated in the body. This study aimed to analyze doxorubicin and doxorubicinol levels in the blood plasma of breast cancer patients. Methods: Participants of this study were 30 breast cancer patients who had received doxorubicin in their therapy regimen. The samples were analyzed using ultra-high performance liquid chromatography-tandem mass spectrometry (LC-MS/MS), with the Acquity UPLC BEH C18 Waters chromatography column (2.1 x 100 mm : 1.7 μm). Plasma (250 μL) samples were prepared by protein precipitation, using methanol. The mobile phase consisted of 0.1% acetic acid (eluent A) and acetonitrile (eluent B), with gradient elution; the flow rate was 0.15 mL/min and runtime, 7 min. Results and Discussion: This method was linear in the range of 1– 1000 ng/mL for doxorubicin and 0.5– 500 ng/mL for doxorubicinol. This method was successfully used to analyze doxorubicin and doxorubicinol, simultaneously, using hexamethylphosphoramide as the internal standard, in the plasma of breast cancer patients. Results showed that the measured concentrations of doxorubicin and doxorubicinol ranged between 12.54– 620.01 ng/mL and 1.10– 27.00 ng/mL, respectively. The measured cumulative doses of doxorubicin ranged between 48.76 and 319.01 mg/m²; thus, the risk of cardiomyopathy in the surveyed patients was under 4%, according to literature.

Lidocaine hydrochloride (LiH), an amide-type local anesthetic agent, is commonly used in dermatological procedures. LiH is categorized as a BCS (biopharmaceutics classification system) class III group, which has high solubility and poor permeability. It should be noted that, in this context, LiH is intended as a local anesthetic, so the level of LiH in systemic circulation should be minimized to avoid toxicity and unwanted side effects such as hypotension and bradycardia. This study aimed to formulate and evaluate LiH-loaded dissolving microneedles (DMNs) with different polymer bases. Moreover, an in vitro permeation study using Franz diffusion cells and in vivo study were also performed. LiH-loaded DMNs were prepared using polymer groups of poly(vinyl pyrrolidone) (PVP-K30) and hyaluronic acid (HA). DMNs were created using the micro-molding method with centrifugation. The formulations selected based on the evaluation were F3 (HA 10%) and F5 (PVP-K30 25%). Based on the in vitro permeation study, the amount of drug permeated and deposited in the skin at F3 (HA 10%) was 247.1 ± 41.85 and 98.35 ± 12.86 μg, respectively. On the other hand, the amount of drug permeated and deposited in the skin at F5 (PVP-K30 25%) was 277.7 ± 55.88 and 59.46 ± 9.25 μg, respectively. Our in vivo drug-permeation study showed that only one rat from the PVP-K30 polymer group—with a concentration of 150.32 ng/mL—was detected on rat plasma. Therefore, LiH can be formulated into a DMN and can be deposited in the skin with a safe concentration of the drug permeating into systemic circulation.

Ketoprofen is an anti-inflammatory agent that may cause gastric irritation if administered orally. Dissolving microneedles (DMN) can be a promising strategy to overcome this issue. However, ketoprofen has a low solubility; therefore, it is essential to enhance its solubility using certain methods, namely nanosuspension (NS) and co-grinding (CG). This research aimed to formulate DMN containing ketoprofen-loaded NS and CG. Ketoprofen NS was formulated with poly(vinyl alcohol) (PVA) at concentrations of 0.5%, 1%, and 2%. CG was prepared by grinding ketoprofen with PVA or poly(vinyl pyrrolidone) (PVP) at different drug–polymer ratios. The manufactured ketoprofen-loaded NS and CG were evaluated in terms of their dissolution profile. The most promising formulation from each system was then formulated into microneedles (MNs). The fabricated MNs were assessed in terms of their physical and chemical properties. An in vitro permeation study using Franz diffusion cells was also carried out. The most promising MN-NS and MN-CG formulations were F4-MN-NS (PVA 5%-PVP 10%), F5-MN-NS (PVA 5%-PVP 15%), F8-MN-CG (PVA 5%-PVP 15%), and F11-MN-CG (PVA 7.5%-PVP 15%), respectively. The cumulative amounts of drug permeated after 24 h for F5-MN-NS and F11-MN-CG were 3.88 ± 0.46 µg and 8.73 ± 1.40 µg, respectively. In conclusion, the combination of DMN with nanosuspension or a co-grinding system may be a promising strategy for delivering ketoprofen transdermally.

An infectious disease, COVID-19, caused by a new type of coronavirus, has been discovered recently. This disease can cause respiratory distress, fever, and fatigue. It still has no drug and vaccine for treatment and prevention. Therefore, WHO recommends that people should stay at home to reduce disease transmission. Due to the quarantine, FDA stated that this could hamper drug development clinical trial protocols. Hence, an alternative sampling method that can be applied at home is needed. Currently, volumetric absorptive microsampling (VAMS) has become attention in its use in clinical and bioanalytical fields. This paper discusses the advantages and challenges that might be found in the use of VAMS as an alternative sampling tool in clinical trials and therapeutic drug monitoring (TDM) during the COVID-19 pandemic. VAMS allows easy sampling, can be done at home, storage and delivery at room temperature, and the volume taken is small and minimally invasive. VAMS is also able to absorb a fixed volume that can increase the accuracy and precision of analytical methods, and reduce the hematocrit effects (HCT). The use of VAMS is expected to be implemented immediately in clinical trials and TDM during this pandemic considering the benefits it has.

Favipiravir and remdesivir are drugs to treat COVID-19. This study aims to find an optimum and validated method for simultaneous analysis of favipiravir and remdesivir in Volumetric Absorptive Microsampling (VAMS) by Ultra High-Performance Liquid Chromatography–Tandem Mass Spectrophotometry. The use of VAMS can be an advantage because the volume of blood is small and the sample preparation process is simple. Sample preparation was done by precipitation of protein using 500 μL of methanol. Analysis was carried out by ultra high-performance liquid chromatography–tandem mass spectrophotometry with ESI+ and MRM with m/z 157.9 > 112.92 for favipiravir, 603.09 > 200.005 for remdesivir, and at m/z 225.968 > 151.991 for acyclovir as the internal standard. The separation was carried out using an Acquity UPLC BEH C₁₈ column (100 × 2.1 mm; 1.7 m), 0.2% formic acid—acetonitrile (50:50), flow rate was 0.15 mL/min, and column temperature was 50°C. The analytical method has been validated with the requirements issued by the Food and Drug Administration (2018) and European Medicine Agency (2011). The calibration range of favipiravir is 0.5–160 μg/mL and 0.002–8 μg/mL for remdesivir.