Sorafenib tosylate (brand name Nexavar)

Sorafenib (formerly called BAY 43-9006, now brand-named Nexavar) is an oral multikinase inhibitor that blocks the RAF kinase and VEGF receptors 2 and 3 to target tumor cell growth and angiogenesis, as well as PDGFR-B, KIT, FLT-3, and RET.  During 2005 it was in clinical trials for kidney cancer and melanoma.   Nexavar was approved by the FDA for use against kidney cancer in December 2005.

Because sorafenib (Nexavar) is FDA-appoved for other diseases, it may be prescribed off-label for GIST patients.  The NCCN Soft Tissue Sarcoma Guidelines version section “SARC-E page, Generally Accepted Systemic Therapy Agents and Regimens” now includes sorafenib as a recommended therapy for GIST resistant to imatinib and sunitinib.  This inclusion may help patients secure insurance coverage for off-label use.  You can access this guide by going to the NCCN website, completing a free registrration and log-in, then clicking on Soft Tissue Sarcoma under the tab for NCCN Clinical Practice Guidelines in Oncology.

Help from Bayer:
The Bayer REACH program for financial assistance with sorafenib will accept GIST patients’ applications even though sorafenib is not yet approved for GIST.  Contact a REACH Program Counselor by calling 1.866.NEXAVAR or 1.87.REACH.4.IT (1.877.322.4448) Monday through Friday from 9 AM to 8 PM EST.  For questions about taking Nexavar, contact the Bayer program called NexConnect.  It’s a 24 hour 7 day a week hotline staffed by oncology nurses. The number is 1-866-Nexavar ( 1 866-639-2827).

LINK HERE for Bayer Nexavar assistance information.

Results for sorafenib (Nexavar) against GIST

Sorafenib Phase II trial results

A GIST trial for sorafenib began in January 2006 at the University of Chicago under the direction of Dr. Hedy Kindler, principal investigator.  The title is “A Phase II Study of BAY 43-9006 for Patients with Imatinib-Resistant Malignant Gastrointestinal Stromal Tumor.”  After approval of sunitinib for GIST the criteria were changed to require that patients have become resistant to both imatinib and sunitinib. This trial has now finished.

A presentation at the GI Cancers Symposium gave final results.  You can click the title below for the full abstract.  The efficacy results in the abstract were:
“Partial response (PR): 13% (1 IM-RES, 4 IM/SU-RES);
Stable disease (SD): 55% (3 IM-RES, 18 IM/SU-RES).
Disease control rate (PR + SD): 68%.
Median progression-free survival: 5.2 mo (95% CI: 3.4, 7.4).
Median overall survival 11.6 mo (95% CI: 8.8, 18.0);
1-year survival 50%; 2-year survival 29%.
Three pts remain on trial receiving study drug (1 PR at 34 mo; 2 SD at 18 and 37 mo).”

Final results of a University of Chicago phase II consortium trial of sorafenib (SOR) in patients (pts) with imatinib (IM)- and sunitinib (SU)-resistant (RES) gastrointestinal stromal tumors (GIST).
J Clin Oncol 29: 2011 (suppl 4; abstr 4)

Clinical Reports of Sorafenib effectiveness for GIST

Two published papers (abstract links below) report response rates in GIST patients treated with sorafenib as third or fourth line or higher.   The multinational study (Montemorro et al) included 124 patients, while the Korean study (Park et al) included 31 patients.  Although these were not clinical trials, the results for both studies and the Phase II trial are similar:

  • partial response rates: 10-13%
  • stable disease rates:  52-57%
  • median progression-free survival (including non-responders): 4.9-6.4 months

Published Papers on Sorafenib for GIST 

Link below to read the abstracts of these papers demonstrating the effectiveness of sorafenib against GIST.

Heinrich MC, Marino-Enriquez A, Presnell A, Donsky RS, Griffith DJ, McKinley A, Patterson J, Taguchi T, Liang CW, Fletcher JA.
Sorafenib inhibits many kinase mutations associated with drug-resistant gastrointestinal stromal tumors.
Mol Cancer Ther. 2012 Aug;11(8):1770-80. doi: 10.1158/1535-7163.MCT-12-0223.
PubMed PMID: 22665524.

Park SH, Ryu MH, Ryoo BY, Im SA, Kwon HC, Lee SS, Park SR, Kang BY, Kang YK.
Sorafenib in patients with metastatic gastrointestinal stromal tumors who failed two or more prior tyrosine kinase inhibitors: a phase II study of Korean gastrointestinal stromal tumors study group.
Invest New Drugs. 2012 Dec;30(6):2377-83. doi: 10.1007/s10637-012-9795-9.
PubMed PMID:22270258.

Montemurro M, Gelderblom H, Bitz U, Schütte J, Blay JY, Joensuu H, Trent J, Bauer S, Rutkowski P, Duffaud F, Pink D.
Sorafenib as third- or fourth-line treatment of advanced gastrointestinal stromal tumour and pretreatment including both imatinib and sunitinib, and nilotinib: A retrospective analysis.
Eur J Cancer. 2012 Nov 6. doi:pii: S0959-8049(12)00808-8. 10.1016/j.ejca.2012.10.009. [Epub ahead of print] PubMed PMID: 23140824.

Manufacturer Information

Development of sorafenib (Nexavar) is co-sponsored by two different pharmaceutical firms:  Bayer and Onyx.

LINKS to relevant information: