Pharmaceutical and Medical Packaging News Magazine
PMPN Article Index

Originally Published March 1998

INDUSTRY WATCH

Do You Have Enough Barrier?

Not all pharmaceutical packages are protecting their contents from moisture and oxygen permeation. Is yours up to the test?

Jim Wagner, Editor-at-Large

With more over-the-counter (OTC) products arriving in stores daily, is it possible that some of these picture-perfect packages fail to protect the product inside? Not with today's standards, you say?

But there are packages on store shelves that do not meet current United States Pharmacopeia (USP) or FDA standards for OTC drugs. The reason is that the containers may not prevent moisture and oxygen permeation over the life of the product. As is common-
ly known, moisture and oxygen can adversely affect potency and dissolution.

According to C. Jeanne Taborsky, a scientific and regulatory affairs consultant who specializes in package testing, engineers are keenly aware of the Code of Federal Regulations that applies to packaging, namely the statement,

"Containers and closures shall not be reactive, additive, or absorptive so as to alter the safety, identity, strength, quality, or purity of the drug beyond the official or established requirements. Container closure systems shall provide adequate protection against foreseeable external factors such as storage and use that can cause deterioration or contamination of the drug product."

But there's a problem, Taborsky noted at the NutraPack conference held January 1998 in Anaheim, CA. Most packages are tested at 25°C and 30% relative humidity (25/60 under ICH guidelines, 40/70 for accelerated shelf life). When drugs are shipped and stored, they can be subjected to higher levels of heat and humidity. The effects can be detrimental to the product.

Taborsky cited one study that showed how three different blister materials performed when temperature and humidity were increased, as in a typical warehouse scenario. The three materials were PVC, PVC/Aclar, and PVC/PVDC. Blister packs were tested at 25/60 (25°C and 60% RH), 30/60, 25/75, and 40/75. Water vapor permeation was measured in milligrams per unit per day per blister.

The study was not designed to pit one structure against another; straight PVC would lose every time. Instead, the study illustrated how each structure fared when temperature and humidity increased. The conclusions were dramatic.

Consider how water vapor permeated the PVC blister. At 25/60, 1.4 mg of water vapor permeated each unit per day. At 30/60, the amount of water vapor increased to nearly 2.0 mg/unit/
day. At 40/75, water vapor permeation was more than twice that of 25/60, increasing to 3.25 mg/unit/day. It's unlikely that a package would be subjected to 40°C (104°F) for any length of time, but Taborsky's point is if that did occur, the efficacy of the drug could be compromised.

In an effort to examine how distribution and storage affects drug packaging, Taborsky is conducting an independent study that will be submitted to USP. (To take part in the study, contact Taborsky at 410/309-0730 or via E-mail at Tabor6333@aol.com.)

Her timing couldn't be better, since more and more OTC products are hitting the shelves. A new study from the consultant group Kline & Co. (Fairfield, NJ) estimates that the OTC market will reach $25.1 billion by 2001 at the retail level as patents expire and drug manufacturers offer OTC versions of their products. Moreover, pharmaceutical companies such as Warner-Lambert, Boehringer Ingelheim, SmithKline Beecham, and American Home Products are introducing nutritional supplements that are complicating matters. The packaging for these products also requires moisture and oxygen protection, but they do not have to meet USP standards. As Taborsky emphasizes, when in doubt, it's better to have maximum moisture and gas protection. The potential consequences of too little protection aren't pleasant.