Combination of bortezomib and panobinostat shows promise against advanced multiple myeloma

In co\continuation of  my update on Bortezomib...

A phase 2 clinical trial has shown that pairing bortezomib with an experimental drug, panobinostat: Panobinostat is a histone deacetylase (HDAC) inhibitor, a type of drug that blocks key processes involved in gene expression and protein degradation. Panobinostat clogs up a protein disposal mechanism in myeloma cells so that harmful byproducts accumulate and eventually cause programmed cell death.(see below structure), may be a promising new treatment for such patients, Dana-Farber Cancer Institute researchers say.

 The PANORAMA 2 trial included 53 patients with relapsed multiple myeloma who had undergone multiple rounds of prior treatment and, in more than half, also stem cell transplant. The researchers reported on 44 patients receiving the panobinostat-bortezomib-dexamethasone combination.

Results showed that in the first phase of the treatment, 9 of the patients had at least a partial response of their disease, and 2 of the 9 saw their myeloma almost disappear, a so-called near complete response. Another 7 patients experienced minimal response, which is also associated with clinical benefit. 

More : http://ash.confex.com/ash/2011/webprogram/Paper41145.html

Proteasome inhibitor bortezomib inhibits T cell-dependent inflammatory responses - a new hope for autoimmune and inflammatory diseases?

In continuation of my update on Bortezomib, I found this info interesting to share with..

Japanese scientists lead by Dr. Koichi Yanaba, of Department of Dermatology at Nagasaki University Graduate School of Biomedical Sciences used mice to show that bortezomib, currently used to treat cancers that affect white blood cells, induces cell death only in harmful (active and proliferating) T cells, leaving the rest unharmed. If the results prove true in humans, it offers hope that this drugs or others similar to it might be used to treat inflammatory diseases without the side effects of current drugs that affect all T cells equally.

To make this discovery, scientists used two groups of mice the first treated with bortezomib and the second with saline. Researchers induced contact hypersensitivity reaction with oxazolone, a chemical allergen used for immunological experiments and found that bortezomib significantly inhibited the contact hypersensitivity responses. Results strongly suggest that bortezomib treatment enhanced T cell death by inhibiting NF-kappa B activation, which plays a key role in regulating the immune response to infection. This in turn led to the suppression of inflammatory responses in immune cells by reducing interferon-gamma production.

"We believe that this new-type remedy for autoimmune and inflammatory disease could successfully treat them in the near future", claims Dr. Koichi Yanaba...

As per the claim by the researchers, bortezomib potently inhibited CHS responses. The attenuation of CHS responses was associated with decreased inflammatory cell infiltration in the challenged skin. Specifically, bortezomib-treated mice showed significantly decreased numbers of CD4⁺ and CD8⁺ T cells in the challenged skin and draining lymph nodes. Cytoplasmic IFN- production by CD4⁺ and CD8⁺ T cells in the draining lymph nodes was decreased substantially by bortezomib treatment. Notably, bortezomib enhanced T cell apoptosis by inhibiting NF-B activation during CHS responses. Thus, bortezomib treatment is likely to induce T cell death, thereby suppressing CHS responses by reducing IFN- production. These findings suggest that bortezomib treatment could be a promising strategy for treating autoimmune and inflammatory disease.

Ref :http://www.jleukbio.org/cgi/content/abstract/88/1/117

New three-drug combination for multiple myeloma ! ...

The regimen, known as RVD, combined the drugs Revlimid - (lenalidomide), Velcade - (bortezomib) and dexamethasone, which previously were found to be highly effective in multiple myeloma patients who had relapsed or no longer responded to first-line therapies.

Fifteen of the 35 newly diagnosed patients in the open-label phase 2 portion of the study subsequently underwent autologous (using their own blood-forming stem cells) transplants, a standard treatment for multiple myeloma and did very well.

For the entire group, after a median 19.3 months of follow up, the median time-to-progression (TTP) of the disease, progression-free survival (PFS), and overall survival (OS) had not yet been reached, according to the presentation. The estimated TTP and PFS at one year are 76 percent, and the estimated one-year overall survival is 100 percent, the results showed.

The more interesting part of the study is that the high response rate was not affected by the specific genetic characteristics of the patients' disease. Patients with so-called "adverse cytogenetics" are at higher risk for treatment failure and death, but in the current study the drug combination worked as well for them as it did in patients with more favorable cytogenetic features.

Except for the main adverse effect, peripheral neuropathy (numbness or pain in the extremities), which typically cleared up after dosages were lowered and the treatment was completed.

The combination has now gone into large phase 3 clinical trials, and the researchers think that this regimen has the potential to be a new standard of treatment in multiple myeloma....

http://www.dana-farber.org/abo/news/press/2009/multiple-myeloma-patients-experience-high-response-rate-with-new-three-drug-combination.html

Carfilzomib for multiple myeloma ?

The proteasome has emerged as an important target for cancer therapy with the approval of bortezomib, a first-in-class, reversible proteasome inhibitor, for relapsed/refractory multiple myeloma (MM). However, many patients have disease that does not respond to bortezomib, whereas others develop resistance, suggesting the need for other inhibitors with enhanced activity. Therefore the researchers evaluated a novel, irreversible, epoxomicin-related proteasome inhibitor - Carfilzomib.

The second-generation proteasome inhibitor carfilzomib is showing noteworthy response rates and low levels of adverse side effects among multiple myeloma patients in a phase II clinical trial.

The updated data from the 17-site study focuses on patients with relapsed or resistant multiple myeloma who have received one to three prior therapies, but not the drug bortezomib, the original proteasome inhibitor. The results are of grat importance because of the fact that multiple myeloma is an incurable, challenging disease with devastating consequences. While new agents are extending life expectancies, they often have adverse side effects, including severe neuropathy. Carfilzomib is showing good response rates, with an improved side effects, except for minor, included fatigue, nausea and anemia.

Ref : http://bloodjournal.hematologylibrary.org/cgi/content/full/110/9/3281/F1

Bortezomib for bone cancer in children & teens..

We knew that Bortezomib marketed as Velcade by Millennium Pharmaceuticals is the first therapeutic proteasome inhibitor to be tested in humans. It is approved in the U.S. for treating relapsed multiple myeloma and mantle cell lymphoma (2008). In multiple myeloma, complete clinical responses have been obtained in patients with otherwise refractory or rapidly advancing disease.

Recently researchers from University of Rochester have found more interesting fact that "bortezomib is effective against bone cancer in human cancer cell studies and in mice". In the current study, researchers sought to use Bortezomib (Velcade) against osteosarcoma, an aggressive cancer that starts in bone, spreads quickly and responds poorly to current chemotherapies. The drug, a proteasome inhibitor.

The researchers are excited because of the fact that "a drug already proven safe and effective in treating the most common cancers of the blood may be equally effective in suppressing bone cancer". Bortezomib caused osteosarcoma cells to self destruct, and prevented their spread. claims the researchers. While further studies are needed, these findings suggest that this drug may represent a new treatment option for a devastating disease and an effective complement to current chemotherapies. Congrats for this achievement.

More : http://www.urmc.rochester.edu/news/story/index.cfm?id=2676