FDA Approval for Ixabepilone

Brand name: Ixempra™       (this is old news)

• Approved for breast cancer

Full prescribing information is available, including clinical trial information, safety, dosing, drug-drug interactions, and contraindications.
On October 16, 2007, the U.S. Food and Drug Administration (FDA) approved ixabepilone for injection (Ixempra™, made by Bristol-Myers Squibb) for the following two indications:

• Ixabepilone is indicated in combination with capecitabine for the treatment of patients with metastatic or locally advanced breast cancer resistant to treatment with an anthracycline and a taxane, or whose cancer is taxane resistant and for whom further anthracycline therapy is contraindicated.
• Ixabepilone is indicated as monotherapy for the treatment of metastatic or locally advanced breast cancer in patients whose tumors are resistant or refractory to anthracyclines, taxanes, and capecitabine.

A randomized, multinational, open-label trial of 752 patients with locally advanced or metastatic breast cancer evaluated the efficacy and safety of ixabepilone (40 mg/m2 IV once every three weeks) plus capecitabine compared to therapy with capecitabine alone. Patients had previously received an anthracycline and a taxane, had evidence of disease progression or resistance, or, in the case of the anthracycline, received a minimum required cumulative dose.
Treatment arms were balanced with regards to prior therapies, disease sites, hormone receptor status and HER2 expression. Patients receiving combination therapy had a statistically significant improvement in progression-free survival (PFS), defined as radiologic progression or death from any cause (hazard ratio 0.69, p<0.0001). The median PFS was 5.7 months in the combination arm and 4.1 months in the capecitabine alone arm. Patients in the combination arm also had an increased objective tumor response rate. Survival data for this trial are not yet mature.
Ixabepilone monotherapy was evaluated in a single arm trial of 126 patients with metastatic or locally advanced breast cancer who had previously received an anthracycline, a taxane and capecitabine, and who had disease progression or, in the case of the anthracycline, received a minimum required cumulative dose. Ixabepilone was administered at the same dose and schedule as in the combination trial. The objective response rate based on independent radiologic review was 12.4 percent (95 percent CI: 6.9, 19.9). The objective response rate based on investigator assessments was 18.3 percent (95 percent CI: 11.9, 26.1). The median response duration was 6.0 months (95 percent CI: 5.0, 7.6).
Treatment with ixabepilone caused new or worsening peripheral neuropathy in approximately 65 percent of patients treated. Grade 3 or 4 peripheral neuropathy occurred in 23 percent of patients treated with ixabepilone and capecitabine, with no grade 3 or 4 peripheral neuropathy reported in the capecitabine arm. In the ixabepilone monotherapy trial, 14 percent experienced grade 3 or 4 peripheral neuropathy. Neuropathy was generally reversible to grade 1 or better with cessation of therapy.
Ixabepilone in combination with capecitabine resulted in a 68 percent incidence of grade 3 or 4 neutropenia compared to 11 percent with capecitabine alone. Twelve patients receiving ixabepilone in combination with capecitabine died from complications arising from neutropenia.
The incidence of neutropenia related deaths was higher in patients with baseline moderate or severe hepatic impairment when treated with both ixabepilone and capecitabine. This combination should not be used in patients with moderate or severe hepatic impairment. When used as monotherapy, 54 percent of patients treated with ixabepilone experienced grade 3 or 4 neutropenia.
Other commonly observed toxicities (>20 percent) included anemia, leukopenia, thrombocytopenia, fatigue/asthenia, myalgia/arthralgia, alopecia, nausea, vomiting, stomatitis/mucositis, diarrhea, and musculoskeletal pain. The following additional reactions occurred in ≥20 percent in the combination treatment arm: palmar-plantar erythrodysesthesia (hand-foot) syndrome, anorexia, abdominal pain, nail disorder, and constipation.

This summary was provided by Richard Pazdur, M.D., director of the FDA's Division of Oncology Drug Products.
The FDA is the division of the U.S. Department of Health and Human Services charged with ensuring the safety and effectiveness of new drugs and other products. (See "Understanding the Approval Process for New Cancer Treatments.") The FDA's mission is to promote and protect the public health by helping safe and effective products to reach the market in a timely way, and monitoring products for continued safety after they are in use.
=====================================================from FDA pages.
Ixabepilone,
from Sorangium cellulosum
promote tumor cell death by causing cell arrest in G2/Mphase.
has unique Beta -tubulin binding site
given 16mg/m2  (Vs 40mg Q21D )weekly for 3 weeks every 4weeks. (with Bevacizumab) or in combination with Xeloda as recommended appears to have been used in clinical trial.

PARP Inhibitors

PARP
Day 2 went very well in Houston
made it on time
in the meantime received positive news from El Paso
can apply for faculty time in clinic at University Medical Center
will be an honor if it gets through'
willing to cover at another Hospital over coming holidays to broaden my share of patients
while veterans physicians take it easy...will use any opportunity to shine.

Now Back to PARP inhibitor, (Poly ADP Ribose Polymerase), they are powerful drugs which follow our first law, they break DNA or cause failure to repair DNA mistakes.  Therefore cause automatic activation of intact P53 to induce automatic cell division Arrest. In other words, they act like Cisplatin and therefore will have a role in Ovarian cancer and by inference, will have a role in basal cell like Breast cancer (or triple negative Breast cancer).   Again, their limitation depend on preservation of P53 and all other molecules of that cascade.  They will also be limited by how fast the cell makes its repair.

Remember the 2nd law is the break of Microtubules/Microfilaments that leads to direct Caspase release, more powerful law.  This implies that a combination of PARP with Taxane (or Ixabepilone or Erubilin)will be the next non platinum combination of significance.

Following this logic, we predict an expanded role to Arsenic trioxyde. But fear of its use resides in its cardiac toxicity. But it acts like a Multikinase inhibitor because it interferes with so many cascades in the signal transduction.  Its limitation could also be that it may not lend itself to combination therapy because of "assumed" risk to the host.

Following-up on the 2nd Law discussed previously

Follow-up on the 2nd law discussed yesterday.
It is not by mistake that the 2 new drugs active in breast cancer, triple negative, target microtubules.
Indeed, both Erubilin and Ixabepilone target Microtubules.
I just took the test on Hope S. Rugo's presentation following the logic, passed the test without problem. So:
SHOULD WE USE CASPASE RELEASE IN LABORATORY AS PROOF OF CHEMOTHERAPY EFFECTIVENESS ON A STANDARD BASE (ROUTINELY), ON FRESHLY OBTAINED TISSUE, THAT IS!

Nature seems to tell us that when there is an error in the gene, we can repair this, but when the Microfilaments are destroyed, Mitosis is compromised and the cells' destiny is to die!  This is where the power of Vinorelbine comes from...Vinorelbine-Cisplatin is used as standard therapy for lung cancer, particularly in other parts of the world! 

DISCUSSION ON PARP INHIBITOR TO FOLLOW...