Paclitaxel (Taxol)

What is Paclitaxel?

Paclitaxel is approved by the U.S. Food and Drug Administration (FDA) for use against breast cancer, non-small cell lung cancer, ovarian cancer, AIDS-related Kaposi’s sarcoma and pancreatic cancer.

Doctors also use it as an experimental or off-label treatment for bladder cancer, esophageal cancer, melanoma, prostate cancer and mesothelioma. Paclitaxel is commonly given in combination with cisplatin or carboplatin.

A 2021 clinical research study concluded that large doses of intraperitoneal paclitaxel, up to 120 mg every month or 60 mg weekly, can be combined with cisplatin and other systemic agents with minimal or no additional hematologic toxicity.

Paclitaxel is an antimicrotubule agent. Microtubules are an essential part of the process by which cells divide. Paclitaxel binds to proteins in cell microtubules, which forces cells to stop dividing. Since cancer cells divide rapidly, their microtubules are a good target for chemotherapy.

This drug dates back to the late 1960s when it was discovered in the bark of the Pacific yew tree. Researchers recognized its potential as an anti-cancer agent, but its natural scarcity made it challenging to market.

More than 20 years later, researchers found a way to produce paclitaxel synthetically. Bristol-Myers Squibb began marketing it as Taxol.

In 2005, the FDA approved a new type of drug called nanoparticle albumin-bound paclitaxel, or nab-paclitaxel. In this formulation, the drug is contained in tiny particles of protein. This improves drug delivery and reduces side effects. Celgene Corporation markets nab-paclitaxel as Abraxane.

Paclitaxel for Pleural Mesothelioma

In the 1990s, studies of paclitaxel (Taxol) as a single agent for pleural mesothelioma showed slight effectiveness. Now researchers are testing nab-paclitaxel (Abraxane) in combination with other drugs.

A 2016 study published in Respirology Case Reports described one medical team’s success in substituting nab-paclitaxel for pemetrexed.

Standard chemotherapy for mesothelioma combines pemetrexed with cisplatin or carboplatin, but pemetrexed is too toxic for some patients. In the case report, a pleural mesothelioma patient responded well to nab-paclitaxel with carboplatin after standard chemotherapy had failed.

In 2017, Clinical Cancer Research published the results of a laboratory experiment using mesothelioma cells. The researchers combined nab-paclitaxel with an experimental immunotoxin called RG7787, with good results.

That same year, Biomedicine & Pharmacotherapy reported on a novel drug delivery method for mesothelioma. The laboratory experiment involved loading paclitaxel into a particular cell type to help the drug reach cancer cells.

Paclitaxel for Peritoneal Mesothelioma

Paclitaxel also shows promise for peritoneal mesothelioma, according to a 2017 European Journal of Surgical Oncology review. The review was co-authored by Dr. Paul Sugarbaker.

Sugarbaker helped pioneer the technique of rinsing a patient’s abdomen with chemotherapy during surgery. This procedure is called hyperthermic intraperitoneal chemotherapy (HIPEC). It is associated with much longer survival times for peritoneal mesothelioma patients.

In the 2017 review, Sugarbaker’s team reported that outcomes are the best for patients who also get long-term paclitaxel. In these follow-up treatments, the drug is delivered to the abdomen to prevent cancer reoccurrence.

Side Effects of Paclitaxel

Like most chemotherapy drugs, paclitaxel damages healthy and cancer cells. Side effects are usually worst about 15 to 21 days after treatment.