Dextran Sulfate: San Francisco Researcher Reports Early Results

On April 20, Donald Abrams M.D. presented early results from the world's only clinical trial of dextran sulfate as a
potential HIV treatment to the County Community Consortium, a group of several dozen physicians in San Francisco. The same data had already been presented to the federal government's AIDS Clinical Treatment Group in Bethesda, Maryland, at the end of March.

This "phase I" (dosage and toxicity) study conducted at San Francisco General Hospital found that patients were able to tolerate all six dosage levels (900 mg per day, 1800, 2700, 3600, 4500, and 5400) for the two-month trial. However, four of the 30 patients were dropped from the study, and six others had their doses reduced, due to reactions which may have been side effects of the drug (see "Dextran Sulfate: Monitoring and Safety", below).

This ongoing study did not find evidence of efficacy in patient data analyzed from the first three doses. T-cells
showed only an insignificant rise. Only one of several patients who were P24 antigen positive (indicating viral activity) at the start of the trial went negative; and one of several who started negative became positive. This lack of improvement in T4 numbers and viral antigen level does not necessarily mean that the drug does not work, because:
* This study was not designed for efficacy. And only 15 patients have been tested so far.
* Only the lower three of the six doses have been analyzed, as the eight weeks of blood work has not been completed for the other patients. The blood work for these patients on the higher doses is being batched for a single run, to be done soon.
* Two months may not have been long enough to show clear changes on the blood tests.
* We do know that patients felt better with the drug. However there was not enough time to register clinical improvement as studies usually measure it, by reduced numbers of opportunistic infections or other incidents.
* These patients used dextran sulfate alone, and the drug may need to be combined with other treatments to be effective.
* The information has not been formally analyzed for this early report. For example, we know that P24 antigen went
negative for only one patient, but we do not know if it decreased for the others.
Dr. Abrams has already written a protocol for "phase II", a study designed to test for efficacy. It will select only
patients who are P24 antigen positive to start, use dose ranges but no placebo, and follow patients long enough to see if
improvements occur.
The phase II study, like the phase I, will test dextran sulfate alone. But Dr. Abrams has also written another
protocol for a trial of dextran sulfate combined with AZT. Theory as well as laboratory evidence suggest that this
combination may be more effective than either drug alone. Combined toxicities are unknown at this time.
Private physicians monitoring patients using dextran sulfate (not part of Abrams' study) have reported encouraging
results. Usually these patients are combining dextran sulfate with low-dose AZT (generally half dose or less), high dose
acyclovir, and often an AL 721 substitute. Usually T-helper cells have shown large increases for those starting with 200 or more; for those with less than 200, T-cell results are inconsistent. Patients also report feeling better, for example
having more energy, and have gained weight. But their physicians believe it is too early to tell whether benefits
will be sustained beyond the five to six months for which data is available.
Dextran sulfate remains a promising treatment possibility--especially in combination with other drugs--but at this time
nobody can be sure whether or not it will prove helpful. Dextran sulfate stops HIV in the laboratory at concentrations
which can be achieved in the bloodstream, suggesting that it might work as a treatment--but not proving that it will.