Abraxane

What is Abraxane?

Abraxane is a powder that is made up into a suspension for infusion (drip into a vein). It contains the active substance paclitaxel attached to a human protein called albumin.
It's used to treat metastatic breast cancer and metastatic cancer of the pancreas.

 

What is Abraxane used for?

Abraxane is used to treat the following cancers in adults:

• metastatic breast cancer when the first treatment has stopped working and standard treatment including an ‘anthracycline’ (another type of cancer medicine) is not suitable. ‘Metastatic’ means that the cancer has spread to other parts of the body.
• metastatic adenocarcinoma (a type of cancer) of the pancreas. Abraxane is used as first treatment in combination with another cancer medicine, gemcitabine.

The medicine can only be obtained with a prescription.

 

How is Abraxane used?

Abraxane should only be given under the supervision of a specialist cancer doctor in units that are specialised in giving ‘cytotoxic’ (cell-killing) medicines. It should not be interchanged with other medicines containing paclitaxel.
Abraxane is given into a vein over a period of 30 minutes.
In metastatic breast cancer Abraxane is given on its own every three weeks. The recommended dose is 260 mg per square metre of body surface area (calculated using the patient’s height and weight).
In metastatic adenocarcinoma of the pancreas Abraxane is given in 4-week treatment cycles. The recommended dose is 125 mg per square metre of body surface area once a day on days 1, 8 and 15 of each cycle. Immediately after giving Abraxane gemcitabine should be given at a dose of 1000 mg per square metre of body surface area.
The dose of Abraxane may be reduced or treatment interrupted in patients who have certain side effects affecting the blood or the nerves.
Patients with severely reduced liver function should not be treated with paclitaxel.

 

How does Abraxane work?

The active substance in Abraxane, paclitaxel, belongs to the group of cancer medicines known as the ‘taxanes’. Paclitaxel blocks a stage of cell division, whereby the internal ‘skeleton’ is dismantled to allow the cell to divide. By keeping the skeleton intact the cells cannot divide and they eventually die. Abraxane also affects non-cancer cells such as blood and nerve cells, which can cause side effects.
Paclitaxel has been available as a cancer medicine since 1993. Conventional types of paclitaxel contain substances that dissolve the paclitaxel, but which can cause hypersensitivity (allergic) reactions. Abraxane does not contain these substances. Instead, the paclitaxel is attached to a human protein called albumin in tiny particles known as ‘nanoparticles’. This makes it easy to prepare a suspension of paclitaxel, which can be infused into a vein. The nanoparticles may also affect the way the medicine is distributed within the body, and therefore its benefits and risks, in comparison with conventional medicines containing paclitaxel.

 

How has Abraxane been studied?

For metastatic breast cancer, Abraxane has been studied in one main study involving 460 women, around three-quarters of whom had received an anthracycline in the past. Around half of the patients in the study had already received treatments for their cancer after it had become metastatic. Abraxane given on its own was compared with a conventional paclitaxel-containing medicine given together with other medicines to reduce side effects. The main measure of effectiveness was the number of patients who ‘responded’ after at least five weeks of treatment. A response was defined as the patient’s main tumours disappearing or shrinking in size by at least 30%.
For metastatic adenocarcinoma of the pancreas, Abraxane was studied in one main study involving 861 patients who received either Abraxane in combination with gemcitabine or gemcitabine alone. The main measure of effectiveness was how long patients lived.

 

What benefit has Abraxane shown during the studies?

In metastatic breast cancer, Abraxane was more effective than conventional paclitaxel-containing medicines. Overall, in the main study, 31% of the women receiving Abraxane responded to treatment (72 out of 229), compared with 16% of the women receiving conventional paclitaxel-containing medicines (37 out of 225).
When looking only at the patients who were receiving their first treatment for metastatic breast cancer, there was no difference between the medicines in terms of measures of effectiveness such as the time until the disease got worse and survival. In contrast, Abraxane was more effective than conventional paclitaxel-containing medicines in patients who had taken other treatments for metastatic breast cancer before. Therefore, the company withdrew its application for the use of Abraxane as first-line treatment during the assessment of the medicine.
In metastatic adenocarcinoma of the pancreas, Abraxane was shown to improve overall survival. Patients survived for around 8.5 months on treatment with the combination of Abraxane and gemcitabine, compared with 6.7 months on gemcitabine alone.

 

What is the risk associated with Abraxane?

The most common important side effects with Abraxane (seen in more than 1 patient in 10) are neutropenia (low levels of neutrophils, a type of white blood cells), gastrointestinal disorders (disorders of the digestive system), peripheral neuropathy (nerve damage including damage to the nerves in the hand and feet), arthralgia (joint pain) and myalgia (muscle pain). For the full list of all side effects reported with Abraxane, see the package leaflet.
Abraxane must not be used in patients who are breast-feeding or who have low levels of neutrophils in the blood before starting treatment.

 

Why has Abraxane been approved?

The Committee for Medicinal Products noted that Abraxane was more effective than conventional paclitaxel-containing medicines in patients with metastatic breast cancer whose first treatment had stopped working, and that, unlike other paclitaxel-containing medicines, patients to be treated with Abraxane do not need pre-treatment with other medicines to prevent hypersensitivity reactions. In addition, Abraxane given in combination with gemcitabine was shown to improve survival in patients with metastatic adenocarcinoma of the pancreas compared with treatment with gemcitabine alone. The Committee decided that Abraxane’s benefits are greater than its risks and recommended that it be given marketing authorisation.

Source: European Medicines Agency