Intraperitoneal injection of paclitaxel (Mitotax) in a single dose of 40 mg/kg was followed by an increase in the number of mitotic granulocytic and erythroid cells, hypoplasia, and pancytopenia of the bone marrow in CBA/CaLac mice. The test preparation decreased the number of hematopoietic precursor cells for erythropoiesis and granulocytopoiesis, but increased the count of polyploid cells and incidence of structural and genomic abnormalities in bone marrow cells. These changes were reversible.

Carboplatin injected intravenously in a maximum permissible dose to Wistar rats inhibited erythro- and granulocytopoiesis in the bone marrow, caused hyporegenerative anemia, leukopenia, and thrombocytopenia in the peripheral blood, led to hypoplasia of the thymus and spleen, and produced moderate apoptosis-inducing effects. These effects were observed within the first month after treatment. In mice carboplatin induced chromatid aberrations in the bone marrow and increased the count of erythrocytes with micronuclei. Moderate hypoplasia of erythro- and granulocytopoiesis and accelerated involution of the thymus were observed 3 and 6 months after cytostatic treatment. Our results indicate that carboplatin possesses higher myelotoxic activity compared to cisplatin.

Preclinical study of the safety of 6 preparations containing ultralow doses of antibodies to endogenous regulators showed that they are relatively safe, are well tolerated by animals in doses more than 1000-fold surpassing the therapeutic dose for humans, and produce no general toxic effect on the organism of laboratory animals.