- Five (38.5%) achieved partial response, as defined as tumor shrinkage of more than 30%
- Seven (53.8%) showed prolonged stable disease (defined as tumor shrinkage <30% from baseline or tumor growth <20% from the nadir)
- Eight (61.5%) had tumor shrinkage
- Five of eight patients (62.5%) who demonstrated either partial responses or prolonged stable disease after treatment with INNO-206 had been previously treated with doxorubicin and had failed to respond.
“The Phase 1b/2 clinical results are exciting and highly supportive of the continued evaluation of INNO-206 as a first-line therapy in patients with advanced soft tissue sarcomas in CytRx’s ongoing international Phase 2b clinical trial,” stated Dr. Chawla. “These data are even more impressive given the advanced stage of disease of the trial patients and the fact that these patients had already either not responded to or relapsed after being treated with, on average, two prior therapies. Additionally the lack of cardiac toxicity thus far is significant, as this reduces the potential for cardiac safety issues that are associated with standard doxorubicin and limits its clinical efficacy. I was impressed by the progression-free survival of approximately 6.4 months, which is longer than the 4.4 month PFS seen with pazopanib treatment in a very similar patient population. Pazopanib, commercially known as Votrient, was recently approved by the FDA as a second-line treatment for soft tissue sarcomas.”“These are powerful results in a very sick patient population. In light of the strength of these results and the fact that there are only limited approved therapies for patients with advanced soft tissue sarcomas, we plan to meet with the FDA to discuss a Phase 3 pivotal trial design with INNO-206 as a third-line therapy in soft tissue sarcoma patients,” said CytRx President and CEO Steven A. Kriegsman. “We have consulted with key thought leaders in the field of soft tissue sarcomas and are preparing a draft clinical trial protocol. If we get approval from the FDA to move forward with this trial, we believe it could be the pivotal study necessary to file for FDA marketing approval, allowing us to eliminate years from the traditional regulatory process.” “CytRx holds exclusive worldwide rights to INNO-206, which is based on a proprietary linker technology that offers multiple potential benefits,” stated CytRx Chief Medical Officer Dr. Daniel Levitt. “This technology allows the agent to concentrate at tumor sites where the delivery molecule is cleaved and the drug, in this instance doxorubicin, is released. The ability to deliver substantially more of the agent directly to the tumor site could improve effectiveness. Further, the drug attached to the linker is inactive until it is cleaved. This occurs at the tumor site and only in one other organ, the bone marrow. Thus, INNO-206 avoids many of the side effects associated with systemic delivery of doxorubicin itself.”
Clinical Trial BackgroundThe Phase 1b/2 clinical trial enrolled a total of 25 patients with advanced solid tumors, the majority of whom had advanced soft tissue sarcoma. These patients had either not responded to or relapsed after treatment with 1 to 3 prior chemotherapy regimens. The initial Phase 1b portion of the trial established the maximum tolerated dose of INNO-206 for this patient population at 350 mg/m 2, which is equivalent to doxorubicin at 260 mg/m 2, or approximate 3.5 times the typical dose (75 mg/m 2) administered to patients with soft tissue sarcoma. Patients in the extended Phase 1b/2 trial were administered up to eight cycles of INNO-206 at the maximum tolerated dose in 21-day intervals. For patients treated at the maximum tolerated dose, the most common grade 3 and 4 adverse events were hematological and included abnormally low neutrophil (white blood cell) counts, a decrease in platelet counts and worsening anemia. One grade 4 febrile neutropenia (fever accompanied with low levels of neutrophils) was reported, and grade 3 adverse events also included two patients with worsening hyponatremia (an electrolyte disturbance) and one patient with dehydration, all of which resolved prior to the start of the subsequent treatment cycle. None of these side effects were unexpected. Soft Tissue Sarcoma Each year in the U.S. nearly 11,000 new cases of soft tissue sarcoma are diagnosed and almost 4,000 deaths are reported due to this cancer. Patients with advanced soft tissue sarcoma who can no longer be treated with surgery and have relapsed or were refractory to prior chemotherapies have a poor prognosis, with fewer than 15% living past five years. CytRx has been granted orphan drug designation by the FDA for the treatment of patients with soft tissue sarcomas. In addition to the Phase 1b/2 clinical trial, CytRx also is conducting a multicenter, international Phase 2b trial with INNO-206 as a first-line treatment for patients with advanced soft tissue sarcoma. This trial is designed to compare therapeutic treatment with INNO-206 head-to-head with doxorubicin with the goal of proving the superiority of INNO-206. Enrollment and analysis of the trial is expected to be completed in 2013. Dr. Chawla also is acting as principal investigator for this trial.
Other IndicationsCytRx recently initiated a Phase 2 clinical trial evaluating the preliminary efficacy and safety of INNO-206 in patients with advanced pancreatic ductual adenocarcinomas who have progressed after receiving two prior therapies. Daniel Von Hoff, M.D., Physician-in-Chief and Distinguished Professor at the Translational Genomics Research Institute, is serving as the clinical trial's principal investigator. Some data from this trial could be reported as early as the end of 2012. Investor Conference Call CytRx will host an investor conference call accompanied by a slide presentation on Monday, June 4 at 10:00 a.m. Eastern time (7:00 a.m. Pacific time) featuring Dr. Chawla and CytRx management to discuss the clinical trial data and next steps for the INNO-206 program in soft tissue sarcoma. The slide presentation will be available on the homepage of the Company’s website www.cytrx.com. To access the conference call, dial (888) 463-4383 (U.S. and Canada) or (706) 679-5355 (international callers). A webcast and the slide presentation also will be available on the Investor Relations section of the CytRx website. A replay of the call and webcast will begin approximately two hours after the live call has ended. To access the replay, dial (855) 859-2056 (U.S. and Canada) or (404) 537-3406 (international callers) and enter the conference ID number: 77958605. About CytRx Corporation CytRx Corporation is a biopharmaceutical research and development company specializing in oncology. The CytRx oncology pipeline includes three programs in clinical development for cancer indications: INNO-206, tamibarotene and bafetinib. With its tumor-targeted doxorubicin conjugate INNO-206, CytRx has initiated an international Phase 2b clinical trial as a treatment for soft tissue sarcomas, has completed its Phase 1b/2 clinical trial primarily in the same indication, and recently initiated a Phase 2 trial for patients with advanced pancreatic ductual adenocarcinomas. CytRx's pipeline also includes tamibarotene, which it is testing in a double-blind, placebo-controlled, international Phase 2b clinical trial in patients with non-small-cell lung cancer, and which is in a Phase 2 clinical trial as a treatment for acute promyelocytic leukemia (APL). The Company completed its evaluation of bafetinib in the ENABLE Phase 2 clinical trial in high-risk B-cell chronic lymphocytic leukemia (B-CLL), and plans to seek a partner for further development of bafetinib. For more information about the Company, visit www.cytrx.com. Forward-Looking Statements This press release contains forward-looking statements within the meaning of Section 21E of the Securities Exchange Act of 1934, as amended. Such statements involve risks and uncertainties that could cause actual events or results to differ materially from the events or results described in the forward-looking statements, including risks or uncertainties related to the outcome, timing and results of CytRx's clinical trials with INNO-206, including the Phase 2b clinical trial for INNO-206 as a treatment for soft tissue sarcomas and the Phase 2 clinical trial in patients with pancreatic cancer, the risk that any future human testing of INNO-206 might not produce results similar to those seen in the Company’s Phase 1b/2 clinical trial for INNO-206 in patients with advanced solid tumors, uncertainties regarding regulatory approvals for current and future clinical testing, including CytRx’s planned Phase 3 clinical trial for INNO-206, and the scope of the clinical testing that may eventually be required by regulatory authorities, the risk that INNO-206 might not show greater efficacy than doxorubicin notwithstanding the administration of higher doses than the standard of care, the risk that additional longer-term dosing of INNO-206 might cause adverse events not seen to date in CytRx's Phase 1b/2 trial, uncertainties regarding whether INNO-206 effectively targets doxorubicin to tumors, the significant time and expense that will be incurred in developing any of the potential commercial applications for INNO-206, including for soft tissue sarcomas, risks related to CytRx's ability to manufacture its drug candidates, including INNO-206, in a timely fashion, cost-effectively or in commercial quantities in compliance with stringent regulatory requirements, risks related to CytRx's need for additional capital or strategic partnerships to fund its ongoing working capital needs and development efforts, including any future clinical development of INNO-206, and the risks and uncertainties described in the most recent annual and quarterly reports filed by CytRx with the Securities and Exchange Commission and current reports filed since the date of CytRx's most recent annual report. All forward-looking statements are based upon information available to CytRx on the date the statements are first published. CytRx undertakes no obligation to publicly update or revise any forward-looking statements, whether as a result of new information, future events or otherwise.