Drugs for Long Acting Injections and Implants

Abstract

Long acting injections and implants have been developed for controlled drug delivery to improve therapeutic effects, decrease dosing frequency, and also avoid potential drug toxicity. Many pharmaceutical agents, such as biomacromolecules (e.g. peptides, proteins and gene therapeutics), drugs with poor bioavailability, and drugs for local delivery are good candidates for developing long acting injections and implants. However, not all drugs are suitable for these formulations (for example, drugs with high dose or narrow therapeutic index). IntroductionDrug formulations should deliver the API (active pharmaceutical agent) to the site of action at the correct therapeutic concentration for as long as the treatment is desired. The therapeutic and the physicochemical properties of a drug determine the preferred route of administration (oral or parenteral) as well as the most appropriate delivery systems.Due to convenience and patient acceptability, oral drug delivery is the most attractive and preferred route for administering medicines. However, some drugs cannot be tolerated via the oral route due to the acid environment and the variety of proteolytic enzymes (proteases) in the gastrointestinal tract (GIT). These conditions tend to degrade or metabolize drugs such as proteins and peptides, resulting in low bioavailability [ 1 ] . Moreover, patients who are unable to tolerate oral ingestion (e.g. patients with aspiration problems or GI disorders) require nonoral administration (e.g. parenteral administration) to receive medications and nutrition. Parenteral administration (e.g. intravenous, intramuscular, and subcutaneous) is also useful

Development of a Poly (lactic-co-glycolic acid) Particle Vaccine to Protect Against House Dust Mite Induced Allergy

“…Polymer particles offer multiple advantages over soluble vaccine systems. They are stable at 4°C for more than a week (36) and protect the encapsulated antigen from degradation after systemic injection (46,47). In addition, particle-based vaccines are proposed to mimic bacterial or viral infections which are readily phagocytosed by DCs for antigen presentation to T cells (48).…”

Non-eroding drug-releasing implants with ordered nanoporous and nanotubular structures: concepts for controlling drug release

“…Encapsulating potent drugs in nano-carriers such as micelles prior to their loading in TNT has been proposed as a prospective solution. 124 The nano-carriers are expected to have a smaller diameter compared to pore diameters of the implants. By this approach, we aimed to achieve LDDS based on NAA and TNT with considerably extended drug-release using polymeric micelles as nano-carriers to encapsulate drugs.…”

Polymeric long-acting drug delivery systems (LADDS) for treatment of chronic diseases: Inserts, patches, wafers, and implants

“…For example, some patients do not get the expected benefit of using antipsychotic drugs. Recurrent relapses and frequent hospitalization due to exacerbations have been reported with conventional drug therapy [28].…”

“…Biopharmaceuticals (biologicals or biologics), include proteins, peptides, nucleic acids, vaccines, gene therapy, living cells, blood products or tissues that have therapeutic applications. One class of biologics that is of particular importance to suppress pathological neovascularization and is of clinical value in cancer, and retinal diseases is the anti-vascular endothelial growth factor (anti-VEGF) [28]. LADDDS are likely to improve efficacy and safety of such biopharmaceuticals [32].…”

“…Other drugs that can be considered for formulation as LADDS include antipsychotics, anticancer drugs, contraceptive and anti-inflammatory steroids. LADDS can promote improved local drug delivery to specific organs (brain , joint, anterior and posterior segments of the eye) [28,36,37]. As discussed earlier, intracranial placement of Gliadel ® wafer is a well-established adjunct therapy to surgery for glioblastoma patients; it offers an increased survival rate and reduced number of deaths compared with placebo [38].…”