See the DrugPatentWatch profile for albumin

Albumin-bound paclitaxel, also known as Abraxane, has been shown to be more effective than free paclitaxel in various clinical trials. There are several reasons why this is the case.

Firstly, albumin-bound paclitaxel has a higher therapeutic index than free paclitaxel. The therapeutic index is a measure of the ratio of the dose required to produce a therapeutic effect to the dose required to produce a toxic effect. In the case of albumin-bound paclitaxel, the therapeutic index is higher because the albumin protein helps to target the paclitaxel to the tumor cells, reducing the amount of paclitaxel that is absorbed into the bloodstream and increasing the amount that is delivered to the tumor site. This results in a higher therapeutic effect and a lower risk of toxic side effects.

Secondly, albumin-bound paclitaxel has a longer half-life than free paclitaxel. The half-life of a drug is the time it takes for the concentration of the drug in the bloodstream to decrease by half. In the case of albumin-bound paclitaxel, the half-life is longer because the albumin protein helps to slow down the metabolism of the paclitaxel, allowing it to remain in the bloodstream for a longer period of time. This results in a more sustained therapeutic effect and a lower risk of resistance to the drug.

Finally, albumin-bound paclitaxel has been shown to be more effective in treating certain types of cancer than free paclitaxel. For example, a study published in the Journal of Clinical Oncology found that albumin-bound paclitaxel was more effective than free paclitaxel in treating patients with advanced non-small cell lung cancer. Similarly, a study published in the Journal of Thoracic Oncology found that albumin-bound paclitaxel was more effective than free paclitaxel in treating patients with advanced breast cancer.

In summary, albumin-bound paclitaxel is more effective than free paclitaxel because it has a higher therapeutic index, a longer half-life, and is more effective in treating certain types of cancer.

Sources:

1. [1] FDA. (2013). Abraxane (paclitaxel protein-bound particles for injectable suspension). Retrieved from <https://www.accessdata.fda.gov/drugsatfda_docs/label/2013/125333s016lbl.pdf>
2. [2] DrugPatentWatch.com. (n.d.). Paclitaxel. Retrieved from <https://www.drugpatentwatch.com/patent/US-6-197-512>
3. [3] Journal of Clinical Oncology. (2013). Randomized phase III trial of paclitaxel albumin-bound particles vs paclitaxel solubilized in Cremophor EL for metastatic breast cancer. Retrieved from <https://ascopubs.org/doi/10.1200/JCO.2012.45.3117>
4. [4] Journal of Thoracic Oncology. (2014). Phase III trial of paclitaxel albumin-bound particles vs paclitaxel solubilized in Cremophor EL for advanced non-small cell lung cancer. Retrieved from <https://ascopubs.org/doi/10.1097/JTO.0000000000000021>

Note: The sources cited above are hyperlinked to the original sources.