Development and Characterization of Olaparib-Loaded Solid Self-Nanoemulsifying Drug Delivery System (S-SNEDDS) for Pharmaceutical Applications.

This study aims to enhance the solubility of Olaparib, classified as biopharmaceutical classification system (BCS) class IV due to its low solubility and bioavailability using a solid self-nanoemulsifying drug delivery system (S-SNEDDS). For this purpose, SNEDDS formulations were created using Capmul MCM as the oil, Tween 80 as the surfactant, and PEG 400 as the co-surfactant. The SNEDDS formulation containing olaparib (OLS-352), selected as the optimal formulation, showed a mean droplet size of 87.0 ± 0.4 nm and drug content of 5.53 ± 0.09%. OLS-352 also demonstrated anticancer activity against commonly studied ovarian (SK-OV-3) and breast (MCF-7) cancer cell lines. Aerosil® 200 and polyvinylpyrrolidone (PVP) K30 were selected as solid carriers, and S-SNEDDS formulations were prepared using the spray drying method. The drug concentration in S-SNEDDS showed no significant changes (98.4 ± 0.30%, 25℃) with temperature fluctuations during the 4-week period, demonstrating improved storage stability compared to liquid SNEDDS (L-SNEDDS). Dissolution tests under simulated gastric and intestinal conditions revealed enhanced drug release profiles compared to those of the raw drug. Additionally, the S-SNEDDS formulation showed a fourfold greater absorption in the Caco-2 assay than the raw drug, suggesting that S-SNEDDS could improve the oral bioavailability of poorly soluble drugs like olaparib, thus enhancing therapeutic outcomes. Furthermore, this study holds significance in crafting a potent and cost-effective pharmaceutical formulation tailored for the oral delivery of poorly soluble drugs.

Evaluation of pharmacokinetic and pharmacodynamic profiles of liposomes for the cell type-specific delivery of small molecule drugs.

Liposome-based drug formulations represent an exciting avenue of research as they increase efficacy to toxicity ratios. Current formulations rely on passive accumulation to the disease site where drug is taken up by the cells. Ligand mediated targeting increases the net accumulation of liposomes, however, an unexplored benefit is to potentially refine pharmacodynamics (PD) of a drug specifically to different cell types within diseased tissue. As a model system, we engineered cardiomyocyte- (I-1) and endothelial-targeted (B-40) liposomes to carry a VEGFR2 inhibitor (PTK787), and examined the effect of cell type-specific delivery on both pharmacokinetics (PK) and PD. Neovascularization in post-myocardial infarction was significantly reduced by B-40 liposomes loaded with PTK787 as compared to animals injected with I-1 liposomes, and profoundly more as compared to free PTK787. This study thus shows that the intraorgan targeting of drugs through cell type-specific delivery holds substantial promise towards lowering the minimal efficacious dose administered systemically.

Nanoscale liposomal formulation of a SYK P-site inhibitor against B-precursor leukemia.

We report preclinical proof of principle for effective treatment of B-precursor acute lymphoblastic leukemia (ALL) by targeting the spleen tyrosine kinase (SYK)-dependent antiapoptotic blast cell survival machinery with a unique nanoscale pharmaceutical composition. This nanoscale liposomal formulation (NLF) contains the pentapeptide mimic 1,4-Bis (9-O dihydroquinidinyl) phthalazine/hydroquinidine 1,4-phathalazinediyl diether (C61) as the first and only selective inhibitor of the substrate binding P-site of SYK. The C61 NLF exhibited a very favorable pharmacokinetic and safety profile in mice, induced apoptosis in primary B-precursor ALL blast cells taken directly from patients as well as in vivo clonogenic ALL xenograft cells, destroyed the in vivo clonogenic fraction of ALL blast cells, and, at nontoxic dose levels, exhibited potent in vivo antileukemic activity against patient-derived ALL cells in xenograft models of aggressive B-precursor ALL. Our findings establish SYK as an attractive molecular target for therapy of B-precursor ALL. Further development of the C61 NLF may provide the foundation for therapeutic innovation against therapy-refractory B-precursor ALL.

Evaluation of Anticancer Efficacy of D-α-Tocopheryl Polyethylene-Glycol Succinate and Soluplus® Mixed Micelles Loaded with Olaparib and Rapamycin Against Ovarian Cancer.

Purpose: Ovarian cancer has the highest mortality rate and lowest survival rate among female reproductive system malignancies. There are treatment options of surgery and chemotherapy, but both are limited. In this study, we developed and evaluated micelles composed of D-α-tocopheryl polyethylene-glycol (PEG) 1000 succinate (TPGS) and Soluplus® (SOL) loaded with olaparib (OLA), a poly(ADP-ribose)polymerase (PARP) inhibitor, and rapamycin (RAPA), a mammalian target of rapamycin (mTOR) inhibitor in ovarian cancer. Methods: We prepared micelles containing different molar ratios of OLA and RAPA embedded in different weight ratios of TPGS and SOL (OLA/RAPA-TPGS/SOL) were prepared and physicochemical characterized. Furthermore, we performed in vitro cytotoxicity experiments of OLA, RAPA, and OLA/RAPA-TPGS/SOL. In vivo toxicity and antitumor efficacy assays were also performed to assess the efficacy of the mixed micellar system. Results: OLA/RAPA-TPGS/SOL containing a 4:1 TPGS:SOL weight ratio and a 2:3 OLA:RAPA molar ratio showed synergistic effects and were optimized. The drug encapsulation efficiency of this formulation was >65%, and the physicochemical properties were sustained for 180 days. Moreover, the formulation had a high cell uptake rate and significantly inhibited cell migration (**p < 0.01). In the in vivo toxicity test, no toxicity was observed, with the exception of the high dose group. Furthermore, OLA/RAPA-TPGS/SOL markedly inhibited tumor spheroid and tumor growth in vivo. Conclusion: Compared to the control, OLA/RAPA-TPGS/SOL showed significant tumor inhibition. These findings lay a foundation for the use of TPGS/SOL mixed micelles loaded with OLA and RAPA in the treatment of ovarian cancer.

Evaluation of the drug release patterns and long term stability of aqueous and organic coated pellets by using blends of enteric and gastrointestinal insoluble polymers.

The major aim of this study was to identify an efficient tool to adjust drug release patterns from aqueous and organic ethylcellulose (a gastrointestinal insoluble polymer) coated pellets and to evaluate the long term stability of the film coatings. Drug release was monitored during open and closed storage at 25 degrees C/60% RH (ambient conditions) and 40 degrees C/75% RH (stress conditions) for up to 24 months. Release of vatalanib succinate, a poorly soluble drug that demonstrates pH-dependent solubility, from pure ethylcellulose coated pellets was slow irrespectively of the type of coating and release medium. By addition of the enteric polymer methacrylic acid/ethyl acrylate copolymer (applied as aqueous Kollicoat MAE 30 DP dispersion or organic solution of Kollicoat MAE 100 P) to ethylcellulose broad ranges of drug release patterns could be achieved. For aqueous film coatings the addition of Kollicoat MAE 30 DP to ethylcellulose dispersions resulted in unaltered drug release kinetics during closed storage at ambient and stress conditions. The storage stabilizing effect of the added enteric polymer might be explained by the more hydrophilic nature of Kollicoat MAE 30 DP compared to ethylcellulose trapping water during film formation and improving polymer particle coalescence. However, during open storage of aqueous coated ethylcellulose:Kollicoat MAE 30 DP pellets at stress conditions drug release decreased due to further gradual polymer particle coalescence. In contrast, drug release rates from organic coated ethylcellulose:Kollicoat MAE 100 P pellets stored at ambient and stress conditions did not change which could be explained by differences in the film formation process. This clearly indicates that the presented concept of the addition of methacrylic acid/ethyl acrylate copolymer to ethylcellulose film coatings in combination with an organic coating process is able to achieve broad ranges of drug release patterns and to overcome storage instability.