Extra breathing space for epinephrine MDI ban

Back in September, the FDA presented proposals to have the 'essential use' designation for epinephrine metered dose inhalers (MDIs) removed, essentially forcing reformulation of current products or the identification of an effective alternative for patients.

The original comment deadline has now been extended until December 19 th , giving stakeholders more time to air their views as to whether epinephrine MDIs should be the latest inhaler-bound treatment to be given the 'no CFCs' treatment.

However, a key issue specific to epinephrine MDIs, is that they are currently available over-the-counter (OTC) in the US, which could make it tricky for patients to find a suitable alternative if reformulation with an alternative propellant is unsuccessful.

A 1978 ruling prohibited the use of CFCs as propellants in any drug or medical device, but the original regulation listed five essential uses exempt from the ban, one of which covered epinephrine MDIs.

However, the FDA has now proposed removing this exemption on the grounds that "there are no substantial technical barriers to formulating epinephrine as a product that does not release [ozone-depleting substances]."

Epinephrine has been approved as an OTC asthma treatment since 1956, and is a widely used OTC medication.

The treatment's OTC status is one aspect of the debate that is making the final decision a little trickier.

"If therapeutic alternatives exist for everyone using the CFC MDI, we would then determine that the CFC MDI does not provide an otherwise unavailable important public health benefit," the FDA's September proposals explain.

"In the case of epinephrine MDIs, the fact that they are marketed over-the-counter, while the therapeutic alternatives for epinephrine MDIs are prescription drugs, makes the analysis of whether everyone is adequately served by therapeutic alternatives more complicated."

Given this concern, the FDA has proposed an extended transition period before which the essential use for epinephrine MDIs would be removed.

The agency took pains to consider how much time would be required to provide patient education for users of OTC epinephrine MDIs (particularly those who do not routinely consult healthcare professionals), as well as whether there is adequate production capacity and supplies available to meet increased demand for therapeutic alternatives once epinephrine MDIs are no longer sold.

As such, the agency settled on a final date of December 31, 2010, but has said it is willing to hear arguments in favour or pushing the date out by another year or so if needs be.

The FDA has also taken into account the fact that albuterol MDIs using hydrofluoroalkane (HFA) as a propellant are a primary therapeutic alternative to OTC epinephrine MDIs, as both drugs are in the same class.

Albuterol (a prescription drug) is in fact the only member of this class of short-acting inhaled beta-agonist bronchodilators available in an HFA MDI, with no drugs in the class available as a dry powder inhaler (DPI).

According to the FDA, sales of OTC epinephrine MDIs are at around 4.5 million units a year.

With albuterol CFC MDIs banned from December 31, 2008, the FDA is of the opinion that albuterol HFA production will be able to meet any increased demand triggered by the epinephrine 2010 cut off.

A public meeting to solicit comments on the proposed ruling is taking place at the FDA's Center for Drug Evaluation and Research on December 5, two weeks before the amended final deadline.