There has been a recent spike in the number of lawsuits against Taxotere maker Sanofi-Aventis over the past four weeks as additional plaintiffs come forward, attributing the permanent loss of their hair to treatment with the chemotherapy drug.

As of mid-March, the number of claims stood at 799. Since then, the U.S. Judicial Panel on Multidistrict Litigation (JPML) reports that 150 additional Taxotere lawsuits have been filed, bringing the current number to 949.

Last fall, all federal lawsuits against the French-based drug company were consolidated before a U.S. District Court in Louisiana. The purpose of consolidation is to make more efficient use of judicial resources by coordinating pre-trial proceedings such as the discovery process as well as witness testimony. This is common practice when numerous lawsuits are filed against a single defendant (or group of defendants) that share a primary cause of action.

Sanofi-Aventis won approval for Taxotere in 1996. Originally approved for the treatment of breast cancer in women, the chemotherapy drug is now used to treat several other types of malignant tumors, including cancer of the prostate, stomach, head and neck and non-small cell lung cancer. Chemotherapy drugs in general cause hair loss (alopecia). However, in most cases, this condition is temporary. Patients see their hair regrow within a few weeks or months after completing their course of treatment.

Plaintiffs in Taxotere litigation allege that the drug caused permanent hair loss. Interestingly, drugmaker Sanofi-Aventis did disclose this possibility to regulators and health care consumers in the E.U. and elsewhere; however, such warnings provided in the U.S. were vague, only stating that “hair generally grows back.” In addition, Sanofi-Aventis made several marketing claims about the superiority of Taxotere, claiming that it was safer and had greater efficacy than competing products. The U.S. Food and Drug Administration later found these claims to be “unsubstantiated,” and the company was ordered to cease and desist.

Also of interest is the fact that Sanofi-Aventis conducted its own study over a decade ago that found permanent alopecia in 3% of patients who were administered the drug. However, follow-up studies found that the actual figure was double that – and even greater when Taxotere was used in combination with other chemotherapy agents. It has only been since December of 2015 that Sanofi-Aventis has been totally forthcoming on its U.S. labels about the true risks of permanent hair loss.

Next month, Taxotere litigation will be moving forward with Science Day scheduled for May 3rd. At that time, all parties to the litigation will present scientific and medical evidence pertinent to the case, which will be evaluated by the court. The following week will see two conferences between the plaintiffs and the defendants in accordance with a court order issued last December in attempts to reach a settlement before the cases go to trial.