Combinatorial delivery of Ribociclib and green tea extract mediated nanostructured lipid carrier for oral delivery for the treatment of breast cancer synchronising in silico, in vitro, and in vivo studies.

PURPOSE: The current research investigated the development and evaluation of dual drug-loaded nanostructure lipidic carriers (NLCs) of green tea extract and Ribociclib. METHOD: In silico study were performed to determine the effectiveness of combinational approach. The prepared NLCs were subjected to in vitro drug release, lipolysis, haemolysis and cell line studies to assess their in vivo prospect. RESULTS: In silico study was done to get docking score of EGCG (-8.98) close to Ribociclib (-10.78) in CDK-4 receptors. The prepared NLCs exhibited particle size (175.80 ± 3.51 nm); PDI (0.571 ± 0.012); and %EE [RBO (80.91 ± 1.66%) and GTE 75.98 ± 2.35%)] respectively. MCF-7 cell lines were used to evaluate the MTT assay, cellular uptake and antioxidant (ROS and SOD) of prepared NLCs. In vitro drug release showed the controlled release up to 72 h. In vitro lipolysis and in vitro haemolysis studies showed the availability of drugs at absorption sites and the greater in vivo prospects of NLCs respectively. Pharmacokinetic study revealed a 3.63-fold and 1.53-fold increment in RBO and GTE bioavailability in female Wistar rats respectively. CONCLUSION: The prominent potential of green tea extract and RBO-loaded NLCs in enhancing their therapeutic efficacy for better treatment of breast cancer.

Directing the Antiretroviral Drugs to the Brain Reservoir: A Nanoformulation Approach for NeuroAIDS.

BACKGROUND: Human immunodeficiency virus (HIV)/AIDS is one of the principal concerns contributing to the global burden and the accompanying deleterious outcomes could not be left unattended. Despite significant advances and innovative research being conducted throughout the globe in order to improve the therapeutic profile of conventionally available antiretroviral (ARV) drugs in the eradication of HIV virus reservoirs, its penetration across the blood-brain barrier (BBB) is still a formidable mission. This makes the central nervous system a dominant and vulnerable site for virus propagation, which ultimately affects the therapeutic potential of the drug administered. Therefore there is an upsurge in the prerequisite of novel technologies to come into play, paving the way for nanotechnology. METHODS: This review primarily provides a comprehensive outline and emphasizes on the nanotechnological techniques employed for the delivery of ARV drugs and their stupendous advantages in overcoming the hurdles associated with the same. RESULTS: The nanotechnological approach bears the potential of site-specific delivery across the BBB via targeting explicit transport processes and provides a sustained release mechanism. Furthermore, different routes of administration explored have also yielded beneficial outcomes for the delivery of ARV drugs. CONCLUSION: The futuristic holistic nanotechnology methods, however, should focus on increasing drug trafficking and permeability across the BBB to ameliorate the therapeutic effect of ARV drugs. Additionally, the domain warrants clinical studies to be undertaken to make the technology commercially viable and a success to deal with the problems of the treatment strategy.

Chitosan coated synergistically engineered nanoemulsion of Ropinirole and nigella oil in the management of Parkinson's disease: Formulation perspective and In vitro and In vivo assessment.

The research presented aims at developing Ropinirole hydrochloride (RHCl) nanoemulsion (NE) with nigella oil for Parkinson's disease (PD). In silico study was done to explore interactions of ropinirole and thymoquinone at receptor site (TNF-α and NFK-ß). Ropinirole and Thymoquinone forms a hydrogen bond with residue Arginine 201 and residue Arginine 253 with a bond length of 1.89 Å and 2.30 Å at the NF-κß receptor. NE was optimized using Central Composite Rotatable Design (CCRD). The globule size of chitosan coated NE, Polydispersity index (PDI) and zeta potential were 183.7 ± 5.2 nm, 0.263 ± 0.005, and 24.9 mV respectively. NE exhibited 85.28% transmittance showing the formulation was clear and transparent. TEM showed that NE had spherical globules with no aggregation. The formulation had a stable pH value of 5.8 ± 0.18. In vitro release and permeation studies exhibited 2 folds and 3.4 folds enhancement when compared with the drug suspension. Neurobehavioral activity and biochemical parameters corroborated well with the pharmacokinetic results. Histopathological study and immunohistochemical analysis were performed to get better picture of 6-OHDA induced toxicity and reversal of PD symptoms. Thus, the NE tailored is a promising synergistic approach yielding enticing outcomes for better management of PD related symptoms.

Targeted Delivery of Natural Bioactives and Lipid-nanocargos against Signaling Pathways Involved in Skin Cancer.

At present, skin cancer is considered a widespread malignancy in human beings. Among diverse population types, Caucasian populations are much more prone to this malignancy in comparison to darker skin populations due to the lack of skin pigmentation. Skin cancer is divided into malignant and non-melanoma skin cancer, which is further categorized as basal and squamous cell carcinoma. Exposure to ultraviolet radiation, chemical carcinogen (polycyclic aromatic hydrocarbons, arsenic, tar, etc.), and viruses (herpes virus, human papillomavirus, and human T-cell leukemia virus type-1) are major contributing factors to skin cancer. There are distinct pathways available through which skin cancer develops, such as the JAK-STAT pathway, Akt pathway, MAPKs signaling pathway, Wnt signaling pathway, to name a few. Currently, several targeted treatments are available, such as monoclonal antibodies, which have dramatically changed the line of treatment of this disease but possess major therapeutic limitations. Thus, many phytochemicals have been evaluated either alone or in combination with the existing synthetic drugs to overcome their limitations and have been found to play a promising role in the prevention and treatment. In this review, a complete overview of skin cancer, starting from the signaling pathways involved, newer developed drugs with their targets and limitations, along with the emerging role of natural products alone or in combination as potent anticancer agents and their molecular mechanism involved has been discussed. Apart from this, various nano-cargos have also been mentioned here, which can play a significant role in the management and treatment of different types of skin cancer.

Natural, Synthetic and their Combinatorial Nanocarriers Based Drug Delivery System in the Treatment Paradigm for Wound Healing Via Dermal Targeting.

A wound refers to the epithelial loss, accompanied by loss of muscle fibers collagen, nerves and bone instigated by surgery, trauma, frictions or by heat. Process of wound healing is a compounded activity of recovering the functional integrity of the damaged tissues. This process is mediated by various cytokines and growth factors usually liberated at the wound site. A plethora of herbal and synthetic drugs, as well as photodynamic therapy, is available to facilitate the process of wound healing. Generally, the systems used for the management of wounds tend to act through covering the ruptured site, reduce pain, inflammation, and prevent the invasion and growth of microorganisms. The available systems are, though, enough to meet these requirements, but the involvement of nanotechnology can ameliorate the performance of these protective coverings. In recent years, nano-based formulations have gained immense popularity among researchers for the wound healing process due to the enhanced benefits they offer over the conventional preparations. Hereupon, this review aims to cover the entire roadmap of wound healing, beginning from the molecular factors involved in the process, the various synthetic and herbal agents, and combination therapy available for the treatment and the current nano-based systems available for delivery through the topical route for wound healing.

A pervasive scientific overview on mangiferin in the prevention and treatment of various diseases with preclinical and clinical updates.

Natural products are increasing used in preventing and treating various diseases. Mangiferin belongs to the xanthone family, and has potential antiangiogenic, anticancer, immunomodulatory and anti-inflammatory activity along with the antioxidant activity. It is also used in the treatment of cardiac problem, diabetes and neurodegenerative disease. Finding of various researchers proves that mangiferin has a broad spectrum therapeutic application. Motive of this review is to describe the various studies performed on mangiferin for its different pharmacological activities. It also discusses various challenges associated with mangiferin such as stability and bioavailability. Strategies and approaches to improve bioavailability of mangiferin have also been discussed. Both research and review articles were used to write the manuscript. They were collected from various search engines like Pub Med, Science Direct and Google Scholar, using keywords like mangiferin, polyphenol, bioavailability enhancement, solubility enhancement, and antioxidant. Mangiferin being a potent antioxidant is effective in the treatment of various diseases. With novel drug delivery approaches we can overcome poor solubility and bioavailability problem which eventually can result to better utilisation of mangiferin in treating a variety of diseases and make mangiferin a revolutionary drug.

Ameliorative effect of a standardized polyherbal combination in methotrexate-induced nephrotoxicity in the rat.

Context: Nephrotoxicity is a renal dysfunction that arises from direct exposure to environmental chemicals or as a side effect of therapeutic drugs. Boerhaavia diffusa Linn. (Nyctaginaceae), Rheum emodi Wall. Ex. Meissn. (Polygonaceae), Nelumbo nucifera Gaertn. (Nelumbonaceae) and Crataeva nurvala Buch-Ham. (Capparidaceae) are well-recognized medicinal plants of Indian traditional system of medicine used for kidney disorders.Objectives: The present investigation was undertaken to develop a chromatographically characterized polyherbal combination and to evaluate its nephroprotective activity.Materials and methods: Roots of B. diffusa and R. emodi, flowers of N. nucifera and stem bark of C. nurvala were extracted by decoction using 70% ethanol. Response surface methodology (RSM) was used for the optimization of extraction parameters. Polyherbal combinations with different doses (150-300 mg/kg) were tested against methotrexate-induced nephrotoxicity in Wistar rats.Results: The optimized extract contained 27% phenols and 15% flavonoids, which showed 75% 1, 1-diphenyl-2-picryl-hydrazyl (DPPH) scavenging potential. Based on the retention time of high-performance liquid chromatography (HPLC) analysis, 17 out of 122 constituents were found common in all extracts and combinations. Two combinations showed significantly higher (p ≤ 0.05) DPPH scavenging potential and xanthine oxidase inhibition. The half maximal inhibitory concentration (IC50) of the best combination for DPPH scavenging and xanthine oxidase inhibition were 80 and 74 µg/mL, respectively. Treatment of methotrexate-induced nephrotoxic rats with polyherbal combination significantly (p ≤ 0.05) improved the kidney function markers, oxidative stress markers and histological parameters.Discussion and conclusion: The developed combination was found to be effective in nephrotoxicity; it can be explored further for the management of drug-induced nephrotoxicity and other chronic kidney diseases.

Cold atmospheric plasma and silymarin nanoemulsion synergistically inhibits human melanoma tumorigenesis via targeting HGF/c-MET downstream pathway.

BACKGROUND: Recent studies claimed the important role of cold atmospheric plasma (CAP) with nanotechnology in cancer treatments. In this study, silymarin nanoemulsion (SN) was used along with air CAP as therapeutic agent to counter human melanoma. METHODS: In this study, we examined the combined treatment of CAP and SN on G-361 human melanoma cells by evaluating cellular toxicity levels, reactive oxygen and nitrogen species (RONS) levels, DNA damage, melanoma-specific markers, apoptosis, caspases and poly ADP-ribose polymerase-1 (PARP-1) levels using flow cytometer. Dual-treatment effects on the epithelial-mesenchymal transition (EMT), Hepatocyte growth factor (HGF/c-MET) pathway, sphere formation and the reversal of EMT were also assessed using western blotting and microscopy respectively. SN and plasma-activated medium (PAM) were applied on tumor growth and body weight and melanoma-specific markers and the mesenchymal markers in the tumor xenograft nude mice model were checked. RESULTS: Co-treatment of SN and air CAP increased the cellular toxicity in a time-dependent manner and shows maximum toxicity at 200 nM in 24 h. Intracellular RONS showed significant generation of ROS (< 3 times) and RNS (< 2.5 times) in dual-treated samples compared to control. DNA damage studies were assessed by estimating the level of γ-H2AX (1.8 times), PD-1 (> 2 times) and DNMT and showed damage in G-361 cells. Increase in Caspase 8,9,3/7 (> 1.5 times), PARP level (2.5 times) and apoptotic genes level were also observed in dual treated group and hence blocking HGF/c-MET pathway. Decrease in EMT markers (E-cadherin, YKL-40, N-cadherin, SNAI1) were seen with simultaneously decline in melanoma cells (BRAF, NAMPT) and stem cells (CD133, ABCB5) markers. In vivo results showed significant reduction in SN with PAM with reduction in tumor weight and size. CONCLUSIONS: The use of air CAP using µ-DBD and the SN can minimize the malignancy effects of melanoma cells by describing HGF/c-MET molecular mechanism of acting on G-361 human melanoma cells and in mice xenografts, possibly leading to suitable targets for innovative anti-melanoma approaches in the future.

Silymarin-loaded nanostructured lipid carrier gel for the treatment of skin cancer.

Aim: The present study was aimed at determining the antiproliferative, antioxidant, anti-inflammatory and antitumor activity of developed silymarin-nanostructured lipid carrier (NLC) gel. Materials & methods: B16 melanoma cell line and albino mice were used as ex vivo and in vivo models, respectively, to evaluate the aforementioned pharmacological activities. Results: The volume of large tumors significantly (p < 0.05) reduced from 5.02 to 3.05 mm3, levels of IL-1α and TNF-α were significantly (p < 0.001) lower and levels of superoxide dismutase (SOD), catalase (CAT) and glutathione (GSH) significantly (p < 0.0001) increased in the group treated with silymarin-NLC gel. Furthermore, in skin treated with placebo and conventional gels, a basosquamous carcinoma and squamous cell carcinoma were noticed, respectively. Conclusion: Silymarin-NLC gel presented better treatment outcomes compared with silymarin-conventional gel.

Nanoemulsions for Improved Efficacy of Phytotherapeutics- A Patent Perspective.

BACKGROUND: Phytoceuticals have been used extensively worldwide due to their reduced toxicity and therapeutic efficacy. The major drawback associated with their delivery which includes lack of sustained action and lipophilicity has been overcome by applications of scientific approach by scientists and researchers. Novel drug delivery systems aimed at enhancing bioavailability, reducing toxicity and in turn improving the patient compliance have been developed with success in recent times. Recent developments in the modern phytopharmaceutical research methods have also solved the major hurdles related to the extraction, identification of constituents in polyherbal systems, and standardisation thereby further facilitating the formulation of improved dosage forms like nanoemulsions with better efficacy of the herbal drugs. METHOD: We did extensive literature review, which included an in depth study and collection of both peer reviewed research and review manuscripts as well as patents related to phytonanoemulsions, which were included in the manuscript. RESULTS: In this article, an attempt has been made to compile the therapeutic and non therapeutic applications of herbal drugs formulated as nanoemulsions, patented phytonanoemulsions, with a discussion on the toxicity and future aspects of the nanoemulsion based delivery of phytotherapeutics. CONCLUSION: The findings of the review confirm that phytonanoemulsions are novel formulations which can be utilized both for therapeutic as well as nontherapeutic applications.

Curcumin-loaded lipid nanocarrier for improving bioavailability, stability and cytotoxicity against malignant glioma cells.

OBJECTIVE: In the present study, Curcumin (CU)-loaded nanocarrier (NC) such as nanoemulsion (NE) was developed with the objective of increasing its cytotoxicity and bioavailability through lymphatic transport by enhancing its solubility and intestinal permeability. MATERIALS AND METHODS: Based on the area obtained in pseudoternary phase diagram, various % combination of Labrafac Lipophile WL 1349, Solutol HS 15, Transcutol HP and distilled water were selected. Formulations which passed physical stability studies were selected for further studies such as globule size, zeta potential, in vitro release, ex vivo permeation, in vitro lipolysis studies, bioavailability studies and cytotoxicity against glioblastoma cells (U-87). RESULT AND DISCUSSION: The optimized NC (NE-SB1) had small average globule diameter of 67 ± 6 nm with zeta potential of -37 ± 2.5 mv which indicated long-term dispersion stability. During in vitro lipolysis study, the digestion rate of medium chain triglycerides increased with decreased globule diameter. Statistically significant difference was found in AUC0-inf of NC formulation (p < 0.05) compared to CU suspension. The relative bioavailability of NC was found 11.88 ± 0.47 with respect to CU suspension. During cytotoxicity studies, IC50 of CU solution on U87 cells was found 24.23 µM, while for the NE- SB1 it was 16.41 µM. The optimized formulation was found to be stable during 6 months of accelerated stability. CONCLUSION: The overall results revealed that the CU-loaded NC is a very effective approach for enhancing the oral absorption of poorly water-soluble drug CU and have great potential for future clinical application.

Omega 3 fatty acid-enriched nanoemulsion of thiocolchicoside for transdermal delivery: formulation, characterization and absorption studies.

Thiocolchicoside (TCC) is an effective therapeutic agent against the orthopaedic, traumatic and rheumatologic disorders but it suffer from the drawback of poor bioavailability due to extensive first pass metabolism and low permeability via the oral route. The aim of the present study was to evaluate the potential of nanoemulsion (NE) for bioavailability enhancement of TCC through the transdermal route. The NEs were developed using Linseed: sefsol in 1:1 ratio as the oil phase, span 80, Transcutol P and distilled water as surfactant, co-surfactant and aqueous phase. Furthermore, selected formulations were subjected to physical stability and consequently evaluated for in vitro permeation using porcine skin. The optimized formulation had small average globule diameter of 117 nm with polydispersity index of 0.285. The globules were spherical in shape as observed by transmission electron microscopy. The in vitro skin permeation profile of optimized NE was compared with aqueous solution of TCC. Significant increase in permeability parameters were observed in NEs formulation (p < 0.05) as compared to aqueous solution of TCC. The steady-state flux (Jss) and permeability coefficient (Kp) for optimized NE formulation (C1) were found to be 30.63 ± 4.18 µg/cm(2)/h and 15.21 × 10(-3) ± 2.81cm(2)/h, respectively. The results of enhanced permeation through transdermal route suggest that water-in-oil NEs which are compatible with the lipophilic sebum environment of the hair follicle facilitate the transport of TCC, and such transport might be predominantly transfollicular in nature. Overall, these results suggested that water-in-oil NEs are good carriers for transdermal delivery of TCC.

Development and validation of HPLC method for simultaneous estimation of piperine and guggulsterones in compound Unani formulation (tablets) and a nanoreservoir system.

An attempt has been made to develop and validate a simultaneous HPLC method for novel approach of drug release via oil-in-water (o/w) nanoemulsion formulation and Habb-e-Khardal Unani tablet containing piperine and guggul sterones E and Z as main ingredients. Nanoemulsion was prepared by titration method using sefsol-218 as an oily phase, cremophor-EL as a surfactant, transcutol as a co-surfactant and distilled water as an aqueous phase. The formulation was optimized on the basis of thermodynamic stability and dispersibilty test. The nanoformulation was evaluated for particle size, surface morphology, electrical conductivity and viscosity determination. The in vitro dissolution was carried out by dialysis bag method. Drugs were quantified using an HPLC method developed in-house with a C(18) column as stationary phase and acetonitrile and water as mobile phase at λ(max) of 240 nm. The optimized formulation showed higher drug release, lower droplet size and less viscosity as compared with the conventional Habb-e-Khardal Unani tablet. The present study illustrated the potential of nanoemulsion dosage form in improving biopharmaceutic performance of piperine and guggul sterone. The HPLC method was also found to be quite sufficient for the routine quality control of formulations containing piperine and guggul sterone E and Z as ingredients and also for in vitro drug release studies.

Nanotherapeutics for Alzheimer's disease (AD): Past, present and future.

Drug delivery to the brain still remains highly challenging for the treatment of Alzheimer's disease (AD). The development of new practical treatment modalities for the treatment of AD is currently a highly active area of research. Our lack of success in the development of effective therapies for AD is attributed to, but not limited to a number of factors including the complexity of the brain. Besides this, it is recognized that AD is multisystemic in nature and this presents numerous difficulties for the potential treatment of these disorders. Another important reason for the lack of development of effective drugs and drug delivery system for AD is inability to deliver drugs effectively to the brain due to the numerous protective barriers surrounding the CNS i.e. blood-brain barrier (BBB), blood-cerebrospinal fluid barrier (BCSFB) and circumventricular organs (CVOs). Solutions to these problems require enhanced novel research activities that can address each of these problems. This review article provides a concise movement into the current and future applications of nanoparticulate drug delivery systems for the treatment of AD and explores the application of nanotechnology in clinical neuroscience to develop innovative therapeutic modalities for the AD.

A two pulse drug delivery system for amoxicillin: an attempt to counter the scourge of bacterial resistance against antibiotics.

Bearing in mind the present scenario of the increasing biological tolerance of bacteria against antibiotics, a time controlled two pulse dosage form of amoxicillin was developed. The compression coating inlay tablet approach was used to deliver the drug in two pulses to different parts of the GIT after a well defined lag time between the two releases. This was made possible by formulating a core containing one of the two drug fractions (intended to be delivered as the second pulse), which was spray coated with a suspension of ethyl cellulose and a hydrophilic but water insoluble agent as a pore former (microcrystalline cellulose). Coating of up to 5% (m/m) was applied over the core tablet, giving a corresponding lag of 3, 5, 7 and 12 h. Increasing the level of coating led to retardation of the water uptake capacity of the core, leading to prolongation of the lag time. Microcrystalline cellulose was used as a hydrophilic but water insoluble porosity modifier in the barrier layer, varying the concentration of which had a significant effect on shortening or prolongation of the lag time. This coated system was further partially compression coated with the remaining drug fraction (to be released as the first immediate release pulse) with a disintegrant, giving a final tablet. The core tablet and the final two pulse inlay tablet were further investigated for their in vitro performance.

Effects of silymarin nanoemulsion against carbon tetrachloride-induced hepatic damage.

Silymarin is a complex mixture of four flavonolignan isomers (silybin, isosilybin, silydianin and silychristin) obtained from 'milk thistle' (Silybum marianum). This plant compound is used almost exclusively for hepatoprotection. Because of its low and poor oral bioavailability, silymarin was formulated as a nanoemulsion to increase its solubility (and so its oral bioavailability) as well as therapeutic activity. The present study assessed the hepatoprotective activity on Wistar rats by determining biochemical parameters and histopathological properties of the nanoemulsion formulation of silymarin against carbon tetrachloride (CCl(4))-induced hepatotoxicity. Hepatoprotective activity was evaluated by the activity of serum alkaline phosphatase, alanine transaminase and aspartate transaminase; antioxidative defence markers (concentration of reduced glutathione); oxidative stress parameter (thiobarbituric acid reactive substances) and liver histopathology. The nanoemulsion-treated group showed significant decreases in glutamate oxaloacetate transaminase, pyruvate transaminase, alkaline phosphotase, total bilirubin and tissue lipid peroxides and increased total protein, albumin, globulin and tissue glutathione as compared to toxicant. The results indicate an excellent potential of the nanoemulsion formulation for the reversal of CCl(4)-induced liver toxicity in rats as compared to standard silymarin.

Conundrum and therapeutic potential of curcumin in drug delivery.

Turmeric, the source of the polyphenolic active compound curcumin (diferuloylmethane), has been used extensively in traditional medicine since ancient times as a household remedy against various diseases, including hepatic disorders, cough, sinusitis, rheumatism, and biliary disorders. In the past few decades, a number of studies have been done on curcumin showing its potential role in treating inflammatory disorders, cardiovascular disease, cancer, AIDS, and neurological disorders. However, the main drawback associated with curcumin is its poor aqueous solubility and stability in gastrointestinal fluids, which leads to poor bioavailability. Multifarious novel drug-delivery approaches, including microemulsions, nanoemulsions, liposomes, solid lipid nanoparticles, microspheres, solid dispersion, polymeric nanoparticles, and self-microemulsifying drug-delivery systems have been used to enhance the bioavailability and tissue-targeting ability of curcumin. These attempts have revealed promising results for enhanced bioavailability and targeting to disease such as cancer, but more extensive research on tissue-targeting and stability-related issues is needed. Tissue targeting and enhanced bioavailability of curcumin using novel drug-delivery methods with minimum side effects will in the near future bring this promising natural product to the forefront of therapy for the treatment of human diseases such as cancer and cardiovascular ailments. We provide a detailed analysis of prominent research in the field of curcumin drug delivery with special emphasis on bioavailability-enhancement approaches and novel drug-delivery system approaches.

Patented herbal formulations and their therapeutic applications.

Recently, there is a greater global interest in non synthetic, natural medicines derived from plant sources due to better tolerance and minimum adverse drug reactions as compared to synthetic medicines. Herbal products are also commonly used by the patients with certain chronic medical conditions, including breast cancer, liver disease, human immunodeficiency, asthma and rheumatological disorders. WHO estimates that about three-quarters of the world's population currently uses herbs and other forms of traditional medicines for the treatment of various diseases. The herbs are formulated in different modern dosage forms, such as Tablets, Capsules, Topical cream, Gel, Ointment and even some novel drug delivery forms, like extended release, sustained release, and microencapsules dosage forms. Patenting of herbal formulations has increased over the past few years and scientific evidence of therapeutic activity has been reported by performing various in vitro and in vivo experiments. This manuscript deals with various patented herbal formulations with their therapeutic application against various diseases.

Chronopharmaceutics: a promising drug delivery finding of the last two decades.

Pulsatile drug delivery system capable of releasing the drug after a predetermined lag period in pulsed or controlled release manner recently has drawn the attention of both academic and industrial research. Depending on the effective therapeutic application of the drug, a variety of design strategies have been formulated in the pursuit of pulsatile release. Circadian (24 hr cycle) dependency of various physiological and pathological functions is well established, thus, it becomes imperative to develop a drug delivery system to achieve release of drug at specific site and time. Such systems are advantageous for drugs which have an extensive first pass metabolism, biological tolerance, needs targeting of locally absorbed / active drug to a specific site in intestine and are useful for the therapy for chronopharmacological needs. This manuscript portrays the important patents related to chronomodulated release system such as system with eroding, rupturing or soluble barrier coatings. In addition, recently developed chronotherapeutic dosage forms including tablets, capsules, pellets, beads implants, osmotic pump, liposome, thermoresponsive, inflammation stimuli sensitive, electrical stimuli sensitive, ultrasound stimuli responsive, magnetic stimuli responsive etc., are also conferred.

Distinctive features of "chronotherapeutic" and "pulsatile" drug delivery systems negating the practice of their interchangeable terminology.

The term pulsatile drug delivery has often been used as a synonym to chronotherapeutic drug delivery. This needs to be given a thought as both the drug delivery systems are entirely addressing different needs of the patients as well as the intentions of the formulators being different. Chronotherapeutic systems are based completely on circadian needs and response of the body and the need of the drug to be in its maximum concentrations at a particular time of the day, the fact being supported by endless list of ailments which elicit the related symptoms at a particular time of the day. Considering the formulation approach, one does not find major differences among site-specific chronotherapeutic systems and the basic and more conventional intestinal or colon targeted systems due to the mechanism and the site of landing of drug of both being almost similar even though the intention of the formulator being different. An ideal pulsatile system is the one delivering drug in different pulses with multiple troughs in release profile. The article explores the major differences in between the two systems and highlights the need of using appropriate terminology for these individual and distinct systems catering different needs.