With growing concerns regarding the cost of cancer care and increased planning and discussion regarding cost issues in healthcare, the use of generic drugs is considered to be a key element of reducing costs. Despite this, the market share of generic drugs is low.
In addition, while most general drugs contain identical active ingredients compared to brand name drugs, that is not true for every generic drugs. When active ingredients vary between generic and brand name drugs, toxicity profiles can be affected.
Researchers in Okayama, Japan, conducted a retrospective analysis to identify the number of patients who had hyponatremia after receiving either the brand name cisplatin or a generic version of cisplatin. The researchers reviewed 79 records in total, 53 records of patients who received brand name cisplatin and 26 records of patients who received generic cisplatin.
The researchers used the records to compare the number of patients who had hyponatremia and renal toxicity. The toxicities were graded the Common Terminology Criteria for Adverse Events, version 4.0 and differences between groups were evaluated using the Student’s t-test, and the odds ratio for hyponatremia was estimated via logistic regression analysis. The researchers found that patients in both groups had significantly increased serum creatinine levels after they received either form of chemotherapy.
However, grade 3 or higher hyponatremia was seen in 30.7% of the generic cisplatin group compared with the 15.1% in the brand name cisplatin group. A multivariate analysis was conducted and revealed that the use of generic cisplatin increased the incidence of hyponatremia (odds ratio=5.661, 95% confidence interval 1.403, 22.839; P=0.015).
The researchers concluded that oncologists should be aware of the potential for an increased risk of hyponatremia in patients receiving generic cisplatin.
The researchers retrospectively investigated the incidence of hyponatremia in patients receiving brand-name cisplatin (CDDP) and a generic counterpart thereof. Oncologists should be aware that use of a generic CDDP might be associated with more hyponatremia than would use of brand-name CDDP.