Notice to Readers Pentamidine Methanesulfonate to be
Distributed by CDC
Pentamidine is used to treat patients with Pneumocystis carinii
pneumonia (PCP) who have failed to respond or who have had adverse
reactions to trimethoprim/sulfamethoxazole. Because of the
unavailability of an approved product and the infrequent demand for
the drug in the United States, CDC has supplied pentamidine through
its Parasitic Disease Drug Service as an Investigational New Drug.
The current incidence of acquired immunodeficiency syndrome (AIDS)
has
created an unprecedented demand for pentamidine (approximately 60%
of
AIDS patients develop PCP).
Starting in late May or early June 1984, CDC will distribute
pentamidine methanesulfonate instead of pentamidine isethionate.
Physicians and pharmacists should be aware of the change, because
the
dosages of the two pentamidine salts are calculated differently
(Table
1). The change from one pentamidine salt to another is necessary
because CDC has been unable to obtain assurances that the
manufacturer
of the isethionate salt can meet the increasing U.S. demand for
pentamidine.
The indications for using pentamidine methanesulfonate are the
same as those for pentamidine isethionate. Physicians in France
and
Canada have used pentamidine methanesulfonate to treat AIDS
patients
with PCP. Although results of such therapy have not been
published,
conversations by CDC with Canadian physicians concerning the
outcomes
of 13 AIDS patients with PCP treated with pentamidine
methanesulfonate
indicate that the efficacy and toxicity of the methanesulfonate
salt
appear similar to those of the isethionate salt. One published
report
has suggested that hypoglycemia occurs more commonly with
pentamidine
methanesulfonate than with pentamidine isethionate, but the number
of
patients described was small (1). The LD((50)) for mice is
approximately the same for the two salts (2).
The doses of the two drugs are calculated differently because
of
the way the manufacturers have labeled their products (Table 1).
Pentamidine isethionate is labeled to reflect the weight of salt
present (pentamidine base moiety plus isethionate salt moieties),
whereas pentamidine methanesulfonate is labeled according to the
weight of only the pentamidine base present. Thus, 2.3 mg/kg of
pentamidine base is equivalent to 4.0 mg/kg of pentamidine
isethionate
salt. Each ampule of pentamidine methanesulfonate solution
contains
the equivalent of 120 mg of pentamidine base dissolved in 3.0 ml of
sterile water for injection. Expressed in terms of volume, the
dose
of pentamidine methanesulfonate is 0.0575 ml/kg.
The procedure for obtaining pentamidine methanesulfonate from
CDC
will be the same as that used in the past to obtain pentamidine
isethionate.
Reported by Div of Anti-Infective Drug Products, National Center
for
Drug and Biologics, US Food and Drug Administration; Div of
Parasitic
Diseases, Center for Infectious Diseases, CDC.
References
Belehu A, Naafs B. Diabetes mellitus associated with
pentamidine
mesylate (Letter to the Editor). Lancet 1982;I:1463-4.
Specia, Paris, France. Unpublished data.
Disclaimer
All MMWR HTML documents published before January 1993 are electronic conversions from ASCII text into HTML. This conversion may have resulted in character translation or format errors in the HTML version. Users should not rely on this HTML document, but are referred to the original MMWR paper copy for the official text, figures, and tables. An original paper copy of this issue can be obtained from the Superintendent of Documents, U.S. Government Printing Office (GPO), Washington, DC 20402-9371; telephone: (202) 512-1800. Contact GPO for current prices.
**Questions or messages regarding errors in formatting should be addressed to [email protected].
