Chlorambucil in the treatment of patients with immune-mediated rheumatic diseases

Recent advances of cocktail chemotherapy by combination drug delivery systems

Combination chemotherapy is widely exploited for enhanced cancer treatment in the clinic. However, the traditional cocktail administration of combination regimens often suffers from varying pharmacokinetics among different drugs. The emergence of nanotechnology offers an unparalleled opportunity for developing advanced combination drug delivery strategies with the ability to encapsulate various drugs simultaneously and unify the pharmacokinetics of each drug. This review surveys the most recent advances in combination delivery of multiple small molecule chemotherapeutics using nanocarriers. The mechanisms underlying combination chemotherapy, including the synergistic, additive and potentiation effects, are also discussed with typical examples. We further highlight the sequential and site-specific co-delivery strategies, which provide new guidelines for development of programmable combination drug delivery systems. Clinical outlook and challenges are also discussed in the end.

Lethal encephalitozoonosis in cyclophosphamide-treated rabbits

Encephalitozoonosis is an opportunistic infection in animals and humans. Its clinical form is observed in immunosuppressed hosts. We studied the occurrence of the manifest form of rabbit microsporidiosis under cyclophosphamide immunomodulation in 40 New Zealand rabbits. The experimental animals were intraperitoneally infected with 5 x 10(7) Encephalitozoon cuniculi spores. Two weeks after infection the animals were treated intraperitoneally with cyclophosphamide, first with 50 mg/kg and then with 15 mg/kg weekly during the 12-week experimental period. Positive controls were either E. cuniculi-infected or cyclophosphamide-immunosuppressed animals. The negative control rabbits remained untreated. Both clinical signs of encephalitozoonosis and depression of peripheral blood cell count developed between weeks 4 and 6 in the experimental animals which died during week 6 of the experiment. No clinical signs compatible with encephalitozoonosis were observed in any of the controls. The results suggest that immunosuppression induced by cyclophosphamide can give rise to a lethal form of encephalitozoonosis.

Chlorambucil is an effective corticosteroid-sparing agent for recalcitrant pyoderma gangrenosum

BACKGROUND

Pyoderma gangrenosum (PG) may fail to respond to corticosteroids. Immunosuppressive and cytotoxic agents are useful in patients with recalcitrant disease. We describe our experiences with chlorambucil for PG.

OBJECTIVE

Our purpose was to evaluate the effectiveness of oral chlorambucil in patients with PG recalcitrant to treatment with prednisone, immunosuppressive therapy, or both.

METHODS

Six patients with recalcitrant PG were given oral chlorambucil 2 to 4 mg/day. Four patients were treated with a combination of prednisone and chlorambucil, and two received chlorambucil alone. Response was based on (1) a diminution in the size of the ulcers, or their complete healing, or (2) a decrease in the dose of corticosteroid therapy.

RESULTS

Beneficial effects were noted within 6 to 8 weeks in all six patients, and corticosteroids were eventually discontinued in all patients. Currently only two patients are still receiving chlorambucil; the other four stopped chlorambucil after 6 to 24 months of treatment. Their disease has remained in remission for 4 to 9 years. Relapse of disease occurred within 1 to 4 months after stopping therapy in one of the two remaining patients or reducing the dose in the other. In both patients, the disease is again responding to treatment. Minimal chlorambucil toxicity has been noted, consisting of leukopenia in one patient.

CONCLUSION

Our findings suggest that chlorambucil is an effective corticosteroid-sparing agent for the control of PG.