Why Long Acting Injectables?

1. To reduce the number of injections needed

For products that are not orally bioavailable, injections are often required. Use of an LAI formulation can be a solution to the inconvenience and discomfort of frequent injections. Examples: leuprolide/Lupron Depot; octreotide/Sandostatin LAR

2. To target delivery of the drug to specific anatomical areas

LAI formulations enable the delivery of drugs to targeted areas such as the knee, eye, ear, and others. Higher drug concentrations can be maintained in the targeted area, thus reducing systemic exposure. Examples: triamcilolone LAI in the knee; nimodipine in the brain.

3. To improve patient compliance

LAI formulations can be used to improve patient compliance in situations where this is an issue. Once the drug is injected, the medication will release for the duration of the formulation. Examples: risperidone/Risperdal Consta; naltrexone/Vivitrol

4. To prevent drug abuse

For drugs that are subject to abuse, an LAI formulation administered by a healthcare professional can reduce the possibility of using excessive amounts or diverting the drug to others. Example: buprenorphine/Sublocade

Product Characteristics

Oakwood develops LAI formulations based upon our technology platform Chroniject™. Below are some of the characteristics of our products:

  • Durations of release: 1 week to 1 year
  • Easily syringable with 18 to 23 gauge needle
  • Reconstitutes immediately with sterile water
  • Good stability characteristics
  • Filled asceptically and terminally sterilized if feasible
  • Proven content uniformity
  • Proven free of foreign particulate matter
  • Microsphere-based, biodegradable polymers such as PLA, PLGA, and other polymers with demonstrated low toxicity, and sourced from multiple suppliers
  • Finished dosage form typically consist of a lyophilized vial containing microspheres, a suspending agent and other excipients

Commercial Considerations

  • LAI formulations are typically for chronic use and command a premium price, with little or no generic competition even after patent expiry, resulting in large sustainable markets.
  • LAI formulations can be used to extend exclusivity of products nearing the end of patent life.
  • Novel, patent protected products can be developed from existing generic drugs, using a 505(b)(2) regulatory approach, at far less cost than developing a New Chemical Entity.

Limitations of Use

1. Size of dose

The maximum injection volume of is typically in the are of 4 ml, although 2 ml is generally preferred. The theoretical feasibility of an LAI dose depends on a number of factors, including the potency of the API, the duration of release desired, the potential maximum drug load of the microspheres, the half life of the drug, and if currently an oral product, the biovailability of the oral form.

2. Side effects and inability to discontinue therapy

If a drug has serious side effects which may require discontinuation of treatment, an LAI formulation may not be appropriate.