Formulations for respiratory tract administration

Abstract

A dosage form for intranasal and / or inhalation administration of an analgesic having low opioid receptor binding activity to a warm blooded animal, that includes a pharmaceutically effective amount of the analgesic. A preferred analgesic is tramadol, a tramadol and / or a pharmaceutically acceptable salt, metabolite or derivative thereof. Methods of making and using the formulation according to the invention are also provided.

Description

[0001] The present invention relates to formulations and methods for the intranasal and inhalation administration of analgesics having low opioid receptor binding affinity.[0002] Pharmacologically active compounds are most commonly administered by the oral route. In particular, analgesics are preferably taken by mouth. However, this convenient route of administration is not always possible for certain patients. Contraindications to oral administration of analgesics can include nausea and / or emesis, oral or gastrointestinal surgery and dysphagia. In addition, rate of analgesia onset is slower and more variable due to first pass effects which compromise the apparent potency of some analgesics and complicate their use. The alternative of administration by injection, e.g., parenteral, intramuscular or subcutaneous injection, is generally not preferred due to patient discomfort and the attendant increased costs associated with the production of and administration of injectable products.[...

AI Technical Summary

Benefits of technology

[0034] The finely divided drug powder is often administered as a composition comprising a blend or mixture of the medicament with an inert carrier. Usually the inert carrier has a mean particle size substantially larger than that of the drug. This provides, among other advantages, an improvement in the flow properties and dispensing accuracy of the composition.

Problems solved by technology

However, this convenient route of administration is not always possible for certain patients.

In addition, rate of analgesia onset is slower and more variable due to first pass effects which compromise the apparent potency of some analgesics and complicate their use.

The alternative of administration by injection, e.g., parenteral, intramuscular or subcutaneous injection, is generally not preferred due to patient discomfort and the attendant increased costs associated with the production of and administration of injectable products.

In addition, only those opioid compounds for which oral delivery was variable and problematic were generally considered for intranasal delivery.

The opioid compounds disclosed to be intranasally effective by Hussain are morphine-like compounds retaining a phenolic group, that are also of high potency (typically exhibiting high mu receptor potency, whether agonist, antagonist or mixed agonist / antagonist) and are stated to be rarely used orally because of inefficient and variable absorption by that route.

However, Hussain does not teach the intranasal administration of analgesics that are either weak opioids or non-opioid analgesics, which are also well absorbed orally with predictable efficacy.

Thus, Frost does not disclose or suggest any systemic delivery of malmefene or any other opioid compound into the blood circulation.

However, the effectiveness of intranasal and / or inhalation administration of a weak opioid or non-opioid analgesic is unpredictable from the disclosures of the intranasal effectiveness of morphine or its derivatives, or meperidine, which are conventional strong opioid receptor binding agents.

Therefore, the art does not disclose that a weak opioid receptor binding compound, such as the analgesic tramadol, or its derivatives and pharmaceutically acceptable salts, can be delivered by transmucosal and / or inhalation administration.

Heretofore there has been no acceptable method or formulation for the transmucosal administration of tramadol, an analgesic which is believed to provide analgesic activity by either or both opioid and non-opioid mechanisms, which is readily absorbed by the oral route and which is not of the highest opioid receptor binding.