– CytRx Corporation (NASDAQ: CYTR), a biopharmaceutical research and development company specializing in oncology, today announced highly positive top-line efficacy results with highly statistical significance from a multicenter, randomized, open-label Global Phase 2b clinical trial investigating the efficacy and safety of aldoxorubicin compared with doxorubicin in subjects with first-line metastatic, locally advanced or unresectable soft tissue sarcomas (STS). Aldoxorubicin combines the chemotherapeutic agent doxorubicin with a novel linker-molecule that binds specifically to albumin in the blood to allow for delivery of higher amounts of doxorubicin (3½ to 4 times) without the major dose-limiting toxicities seen with administration of doxorubicin alone.
In this 123-subject, 31-center global Phase 2b clinical trial, subjects with advanced soft tissue sarcomas were administered either 350 mg/m2 of aldoxorubicin (83 subjects) or 75 mg/m2 of doxorubicin (40 subjects) every 3 weeks for up to 6 cycles. Subjects were followed every 6 weeks with CT scans to monitor tumor size. The primary endpoint was progression-free survival (PFS) as determined by both investigators at study sites and by a blinded radiology review performed at an independent central laboratory. Secondary endpoints included overall response rates (complete and partial) and PFS at 6 months for each group and overall survival which will be reported on when the clinical trial is complete.
In an intent-to-treat analysis, the investigator-assessed PFS was 8.4 months for aldoxorubicin patients versus 4.7 months for doxorubicin patients (p=0.0002), while the blinded central lab review indicated PFS for aldoxorubicin patients was 5.7 months versus 2.8 months for doxorubicin patients (p=0.018). Per investigators, 67.1% of aldoxorubicin patients had not progressed at 6 months, compared with 36.1% of doxorubicin-treated patients. By blinded central lab review, 46.8% of aldoxorubicin patients had not progressed at 6 months, compared with 23.7% of doxorubicin patients.
The overall response rate as determined by the investigators was 25.4% for aldoxorubicin subjects (2.7% complete response and 22.7% partial response) versus 5.4% for doxorubicin subjects (0% complete response and 5.4% partial response). As assessed by blinded central lab review, 23.0% of aldoxorubicin subjects had a partial response while 0% of doxorubicin subjects exhibited any objective response.
As determined by both the trial investigators and by blinded central radiology review, subjects treated with aldoxorubicin demonstrated statistically significant better clinical outcomes than those receiving standard doxorubicin therapy for their soft tissue sarcomas.
"These results are extraordinary for a single agent treating these highly chemotherapy-resistant tumors," said study principal investigator Sant Chawla, M.D. of the Sarcoma Oncology Center in Santa Monica, California. " Aldoxorubicin is the first and only single agent to surpass doxorubicin in treating first line soft tissue sarcomas."
Dr. Chawla added, "Previous results from this trial presented at the Connective Tissue Oncology Meeting in October indicated that subjects treated with aldoxorubicin demonstrated no clinically significant cardiotoxicity whereas doxorubicin shows cardiotoxicity at certain cumulative dose levels, and no subjects left the study due to aldoxorubicin side effects. These findings together suggest that aldoxorubicin could become the treatment of choice for soft tissue sarcomas. Yet this drug's potential extends much further because doxorubicin in particular and anthracyclines in general are indicated as first- or second-line therapy for many other common cancers including breast, ovarian, small-cell lung, multiple myeloma, acute myelocytic leukemia and more. As such, the ability of aldoxorubicin to safely administer high doses of doxorubicin holds tremendous therapeutic potential to oncologists and their patients worldwide."
CytRx President and CEO Steven A. Kriegsman commented, "We believe, quite simply, that aldoxorubicin is a major advance for treating soft tissue sarcomas and are thrilled to be reporting these highly positive top-line results from our Phase 2b trial. We extend gratitude to the investigators who so adeptly managed the conduct of this trial and to the patients and their families who participated in it. These data prove that by applying our proprietary linker technology to target the release of doxorubicin directly at the site of cancer we are able to safely increase the dosage of doxorubicin by approximately three and one-half to four times with tremendous clinical benefit to the patient.
"We remain on track with a robust development program that includes advancing aldoxorubicin into a pivotal Phase 3 trial as second-line therapy in soft tissue sarcomas in the first quarter of 2014 under an FDA special protocol assessment, as well as evaluating aldoxorubicin for the treatment of malignant glioblastoma and HIV-related Kaposi's sarcoma," added Mr. Kriegsman. "Aldoxorubicin is an extremely valuable asset and a powerful driver of value for CytRx and our shareholders. In addition to our current programs, aldoxorubicin is applicable to a wide range of indications including small-cell lung cancer, breast cancer, and ovarian cancer. Furthermore, we believe the results presented today clearly establish our linker technology as a major breakthrough in cancer drug development. Importantly, the potential to use our linker platform to create new chemical entities that extend the patent protection of blockbuster drugs is of great interest to the world's largest pharmaceutical companies, and could lead to partnership and licensing opportunities."
In the Phase 2b clinical trial aldoxorubicin was found to be safe and well tolerated. All adverse events in subjects treated with aldoxorubicin were consistent with the known side effects of doxorubicin, resolved before the administration of the next dose and did not require treatment discontinuation. There were no treatment-related deaths in the aldoxorubicin group but one treatment-related death in the doxorubicin group. In the CytRx study being reported on today, the head-to-head single-agent comparison of aldoxorubicin to doxorubicin was conducted with clinical and scientific rigor and showed a clear superiority of treatment with aldoxorubicin over doxorubicin in advanced soft tissue sarcomas.
Full results from this clinical trial will be submitted for presentation at the 2014 ASCO Annual Meeting, to be held May 30 to June 3, in Chicago, Illinois.
About the Phase 2b Trial Design
The study examined 123 subjects who received either aldoxorubicin or doxorubicin in a 2:1 randomization, respectively. Aldoxorubicin was administered to 83 subjects at a dosage of 350 mg/m2 (doxorubicin equivalents of 260 mg/m2) as a 30-minute intravenous infusion on Day 1 of each cycle, while doxorubicin (75 mg/m2) was administered to 40 subjects as a 5-30 minute infusion on Day 1 of each cycle. A cycle of therapy was defined as a 3-week (21-day) period. Multiple cycles were administered until the subject was withdrawn from therapy or until a maximum of 6 cycles were administered. CT scans were obtained every 6 weeks to assess tumor response and progression, and adverse events were collected in a case report form.
About Soft Tissue Sarcoma
STS is a cancer occurring in muscle, fat, blood vessels, tendons, fibrous tissues and connective tissue, and can arise anywhere in the body at any age. According to the American Cancer Society, there are approximately 50 types of STS; and in 2013 more than 11,400 new cases will be diagnosed in the U.S., and approximately 4,400 Americans will die from STS. In addition, approximately 40,000 new cases and 13,000 deaths in the U.S. and Europe are part of a growing underserved market.
The widely used chemotherapeutic agent doxorubicin is delivered systemically and is highly toxic, which limits its dose to a level below its maximum therapeutic benefit. Doxorubicin also is associated with many side effects, especially the potential for damage to heart muscle at cumulative doses greater than 500 mg/m2. Aldoxorubicin combines doxorubicin with a novel single-molecule linker that binds directly and specifically to circulating albumin, the most plentiful protein in the bloodstream. Protein-hungry tumors concentrate albumin, thus increasing the delivery of the linker molecule with the attached doxorubicin to tumor sites. In the acidic environment of the tumor, but not the neutral environment of healthy tissues, doxorubicin is released. This allows for greater doses (3 ½ to 4 times) of doxorubicin to be administered while reducing its toxic side effects. In studies thus far there has been no evidence of clinically significant effects of aldoxorubicin on heart muscle, even at cumulative doses of drug well in excess of 2 g/m2
Conference Call and Webcast
CytRx management will be hosting a conference call and webcast today beginning at 10:30 a.m. Eastern time. To access the conference call, dial 888-463-4383 (U.S. and Canada) or 706-679-5355 (international callers). A webcast will be available in the investor relations section of the company's website, www.cytrx.com
. 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: 19821609.
About CytRx Corporation
CytRx Corporation is a biopharmaceutical research and development company specializing in oncology. CytRx currently is focused on the clinical development of aldoxorubicin (formerly known as INNO-206), its improved version of the widely used chemotherapeutic agent doxorubicin. CytRx has completed a global Phase 2b clinical trial with aldoxorubicin as a first-line therapy for soft tissue sarcomas, a Phase 1b/2 clinical trial primarily in the same indication, a Phase 1b study of aldoxorubicin in combination with doxorubicin in subjects with advanced solid tumors and a Phase 1b pharmacokinetics clinical trial in subjects with metastatic solid tumors. CytRx plans to initiate under a special protocol assessment a potential pivotal Phase 3 global trial with aldoxorubicin as a therapy for subjects with soft tissue sarcomas whose tumors have progressed following treatment with chemotherapy. CytRx has initiated a Phase 2 clinical trial with aldoxorubicin in subjects with late-stage glioblastoma (brain cancer), and plans to initiate a Phase 2 clinical trial in HIV-related Kaposi's sarcoma. CytRx plans to expand its pipeline of oncology candidates based on a linker platform technology that can be utilized with multiple chemotherapeutic agents and may allow for greater concentration of drug at tumor sites. CytRx also has rights to two additional drug candidates, tamibarotene and bafetinib. CytRx 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 CytRx Corporation, visit www.cytrx.com
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 relating to the outcome, timing and results of CytRx's clinical trials, the risk that any future human testing of aldoxorubicin might not produce results similar to those seen in past human or animal testing, including the clinical study described in this press release, risks related to CytRx's ability to manufacture its drug candidates 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 the Phase 3 clinical development of aldoxorubicin, 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.
Investor Relations Contacts:
David J. Haen
Vice President, Business Development
John M. Columbia
Legend Securities, Inc.
The Sarcoma Oncology Center is proud to announce that Sant P. Chawla M.D. was the lead investigator for denosumab (Xgeva® by Amgen), exciting new drug approved by the FDA on June 13, 2013 for treatment of Giant Cell Tumor of Bone. Dr. Chawla led the Phase II and III investigation of denosumab (Xgeva®) in patients with giant cell tumor of the bone. Dr. Chawla brought with him over two decades of experience in conducting clinical trials. Before this study, he has played a pivotal role in the investigation of over 50 cancer drugs, some of which have been subsequently approved by the FDA, including, to name a few: Carboplatin for the treatment of ovarian cancer (by Bristol-Myer), Emend (Appripitant) for nausea/vomiting (Merck) and Pazopanib (Votrient) for soft tissue sarcoma (Glaxo). Additionally, Dr. Chawla is presently involved in multiple Phase I, Phase II and advanced Phase III trials for solid tumors and sarcomas for consideration by the FDA in the near future.
The following is a message from the FDA's Office of Hematology and Oncology Products Director, Dr. Richard Pazdur:
On June 13, 2013, the U. S. Food and Drug Administration approved denosumab (Xgeva® injection, for subcutaneous use, Amgen Inc.) for the treatment of adults and skeletally mature adolescents with giant cell tumor of bone that is unresectable or where surgical resection is likely to result in severe morbidity.
Denosumab's approval was based on demonstration of durable objective responses observed in two multicenter open label trials enrolling adult and skeletally mature adolescents with histologically confirmed, measurable giant cell tumor of bone. These tumors were either recurrent, unresectable, or were located where planned surgery was likely to result in severe morbidity. Patients received 120 mg denosumab subcutaneously every 4 weeks with additional doses on days 8 and 15 of the first month.
A total of 304 patients received denosumab. The median age was 33 years (range: 13-83 years) and a total of 10 patients were skeletally mature adolescents (13-17 years). Radiographic assessments at baseline and following denosumab treatment were available for 187 (61%) patients. A retrospective determination of objective response was performed by an independent review committee using modified Response Evaluation Criteria in Solid Tumors (RECIST 1.1).
An objective response was identified in 47 of 187 patients for an overall response rate of 25% (95% CI: 19, 32). All responses were partial responses. The estimated median time to response was 3 months. In the 47 patients with an objective response, the median duration of follow-up was 20 months (range: 2- 44 months), and 51% (24/47) had responses lasting at least eight months. Three patients experienced disease progression following an objective response.
Safety data was evaluated in 304 patients with giant cell tumor of bone who received at least one dose of denosumab. Of these patients, 145 were treated for at least one year. The most common adverse reactions were arthralgia, headache, nausea, back pain, fatigue, and pain in the extremity. The most common serious adverse reactions were osteonecrosis of the jaw and osteomyelitis.
The recommended dose and schedule of denosumab for the treatment of giant cell tumor of bone is 120 mg administered subcutaneously every four weeks with additional 120 mg doses on days 8 and 15 of the first month.
Full prescribing information is available at: http://www.accessdata.fda.gov/drugsatfda_docs/label/2013/125320s094lbl.pdf
Healthcare professionals should report all serious adverse events suspected to be associated with the use of any medicine and device to FDA's MedWatch Reporting System by completing a form online at http://www.fda.gov/medwatch/report.htm , by faxing (1-800-FDA-0178) or mailing the postage-paid address form provided online, or by telephone (1-800-FDA-1088).