ATLANTA - Sporadic supply combined with the loss of two major manufacturers, have jeopardized immediate quantities of tetanus and diphtheria toxoid-containing vaccines. If a shortage should occur, the Advisory Committee on Immunization Practices (ACIP) recommended deferring the fourth dose of the diphtheria-tetanus-acellular pertussis (DTaP) vaccine until adequate supply is available. The primary three-dose series should remain unaffected.
Shortages of diphtheria-tetanus toxoids (Td) are expected to last anywhere from the next six to 12 months.
Providers who receive public vaccine are asked not to stockpile more than a 30-day vaccine supply. The Centers for Disease Control and Prevention (CDC) will continue to monitor state orders for DTaP, allocate vaccine as necessary and provide program guidance where needed.
The Td and DTaP supply were hurt in part by the December 2000 decision by Wyeth Lederle to cease production of the DTaP vaccine, Acel-Imune. Baxter Hyland Immuno, formerly North American Vaccine, preceded Wyeth Lederle by pulling out its small but important share in the market, thus leaving Aventis Pasteur and GlaxoSmithKline the only producers in the DTaP market.
Manufacturers blame production issues and the removal of the preservative thimerosal as contributing factors for unfulfilled DTaP vaccine purchase orders.
Barbara Howe, MD, vice president and director, clinical research and medical affairs, vaccines, GlaxoSmithKline, said although the manufacturer cannot supply the entire U.S. market for all five vaccine doses, it can supply the three-dose primary series for its DTaP vaccine, Infanrix.
Phil Hosbach, MD, executive director of public business and immunization policy at Aventis Pasteur, said the manufacturer is working closely with the CDC to identify areas of need in public health for its DTaP vaccine, Tripedia. Hosbach said Aventis Pasteur aims for a 60-40 split in the allocation of Tripedia: 60% to the public sector and 40% to the private sector.
"Based on CDC contracts, the public health need for DTaP not in combination products is between 8.3 million and 11.1 million doses annually," said Dean Mason, chief of the Program Support Branch in the Division of Immunization Services at the National Immunization Program. "The loss of Wyeth Lederle and Baxter Hyland amounts to a production loss of about 2.9 million doses of DTaP vaccine per year, or about 20% of the total CDC market, which does not include the private sector."
According to CDC figures, 42 projects (immunization grantees) totaling 163,500 doses of DTaP are more than 30 days overdue. Since CDC contracts require the vaccine manufacturer to deliver within 15 days of the receipt of order, Mason said the vaccine need is apparent. "This reflects the fact that we are living hand-to-mouth on the DTaP supply at the present time."
CDC figures show nearly 500,000 doses are 14 to 29 days back ordered through CDC's contracts for 47 projects. For 31 projects, 388,000 doses have been ordered in the past 14 days without being filled.
"The bottom line is that CDC has 1.03 million doses on back order," said Mason.
The CDC contracted 8.3 million doses this calendar year, compared with 10.4 million doses purchased in 2000. The total U.S. need is estimated from 15.1 million to 20.4 million doses. The figure is based on ordering history and exceeds the birth cohort and birth need.
"The important question is how much will the two remaining companies produce for calendar year 2001," said Mason.
In total, Aventis Pasteur and GlaxoSmithKline are predicting production of between 21 million and 25 million doses. "If our maximum need will be met, what's the issue? The problem is one of catch-up between the current need and the ability to produce vaccine by the end of the year.
"We may be caught up by the end of the year, but at the present time we are literally waiting on the Food and Drug Administration's Center for Biologics Evaluation and Research lot releases. As soon as those are made, the companies are filling back orders. They're not getting ahead of the curve," said Mason.
GlaxoSmithKline would not provide an estimate of how long Infanrix will be in short supply. Aventis Pasteur expects the shortage of Tripedia will continue for the next six to 12 months; but predicts substantial improvement in the next three to six months.
Aventis Pasteur is screening Td orders, prioritizing shipments to hospitals and trauma centers and limiting the amounts shipped out. They also have a 24-hour hotline and prioritize calls from those caring for people with trauma or wound injuries. Those individuals will receive higher priority than otherwise healthy adolescents receiving a booster dose at age 15.
|Current Back Orders|
The following is the number of projects awaiting DTaP orders through CDC's contracts and the corresponding dose amounts. Thirty-two projects are counted with pending orders in more than one time frame, 11 projects have only one order pending and 20 projects have no orders pending at this time.
|Manufacturer||Projects*||30 days late||Projects||14-29 days late||Projects||<14 days late|
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