While policymakers wrestle with cost and access issues, manufacturers still face difficulties ensuring the quality of vaccine
production. One reason for low utilization of Merck's Zostavax vaccine for shingles has been supply shortages due to manufacturing
problems at Merck's West Point, Pennsylvania, vaccines plant; reports of charred particles in vials have further complicated
remedial efforts. Merck's adult vaccines for hepatitis A and hepatitis B also are in short supply, and the company has stopped
producing its ProQuad varicella-MMR vaccine.
Indian manufacturers seeking to ramp up production of low-cost vaccines also have run into production problems. WHO recently
removed combination vaccines produced by Panacea Biotech from its pre-qualification list due to inspections that found quality
management deficiencies at the firm's plant near Punjab, India.
Meanwhile, FDA has concerns about manufacturing deficiencies and particulate contamination at several vaccine companies. FDA
sent a Warning Letter to Australia-based influenza `dicated that the company had not addressed manufacturing problems identified
at a site visit in April 2010. The initial FDA investigation stemmed from adverse-event reports citing reports of fever and
convulsions in children taking its influenza vaccine in during the 2009–2010 pandemic, but uncovered a number of deficiencies
in recordkeeping and quality control.
The challenges of ensuring vaccine safety and quality were illustrated in 2010 when FDA suspended the marketing of GSK's rotavirus
vaccine, Rotarix, for several months to assess the effect of adventitious porcine virus found in this product. After evaluation,
FDA recommended that physicians continue to use Rotarix, as well as Merck's Rota Teq vaccine, which has a similar problem.
The agency cited strong safety records for the products and no evidence that the viruses pose a safety risk to humans. The
case points to difficulties in adopting advanced analytic technologies that can uncover previously undetectable contaminants.
The challenge for regulators is to weigh the risk of halting vaccination for a dangerous health condition against uncertain
effects of apparently benign extraneous viral material.
Jill Wechsler is Pharmaceutical Technology's Washington editor, 7715 Rocton Ave., Chevy Chase, MD 20815, tel. 301.656.4634, firstname.lastname@example.org
1. B. Deer, British Medical Jrnl., Jan. 5, 2011 and Jan. 19, 2011.
2. A. Wakefield, The Lancet, 35, 637–641 (1998).
3. Editorial Retraction, The Lancet, Feb. 2, 2010.
4. IOM,Adverse Effects of Vaccines (Washington, DC, 2011),