Helix BioPharma Corp. Completes Data Review of First Four Cohorts of Its Phase I/II Clinical Study for Lung Cancer Drug Candidate L-DOS47

AURORA, ON--(Marketwired - Oct 15, 2013) - Helix BioPharma Corp. (TSX: HBP) (FRANKFURT: HBP), a biopharmaceutical company developing innovative drug candidates for the prevention and treatment of cancer, today announced it has completed its interim review of the Company's ongoing Phase I/II clinical safety, tolerability and preliminary efficacy study of L-DOS47 in Poland (the "LDOS002 Study"). This review was not a formal analysis of data, but a review of safety and clinical parameters collected during the study to date.

Enrollment has completed for the first four dosing cohorts. Each cohort enrolled and dosed three patients. Dose levels were increased at each new cohort following a review of safety data from the previous cohort by the Trial Steering Committee. The Cohort 4 dose level of 0.46 micrograms/kg patient body weight is at the lower level of the theoretically calculated minimum effective dose as determined from animal modeling.

All 12 patients treated met study entry criteria and were histologically confirmed non-squamous Non-small Cell Lung Cancer (NSCLC) late stage (Stage IIIb (n=5) or Stage IV (n=7)) patients refractory to previous treatments with approved lines of chemotherapy.

Patients enrolled in the study received a 30 minute intravenous infusion of L-DOS47 weekly for two weeks followed by one weeks' rest (one treatment cycle is 3 weeks). Cycles with L-DOS47 continued until the patient experienced disease progression, unacceptable toxicity, withdrew consent, or completed four treatment cycles and did not wish to continue with additional cycles, whichever occurred first. After four cycles, patients could continue to receive L-DOS47 for as long as there was sustained clinical benefit and it was well tolerated, in the discretion of the treating investigator and in consultation with the medical monitor.

L-DOS47 was well tolerated for all patients treated within all cohorts. None of the treatment-related adverse events reported to date has met the definition of a dose-limiting toxicity. No infusion or anaphylactic reactions have been reported. Adverse events reported to date are those normally expected for the population under study.

A review of available pharmacokinetic (PK) and immunogenicity data showed that these data so far are consistent with trends seen within pre-clinical animal studies of L-DOS47. A formal PK analysis will be conducted pending the collection of all PK data at the completion of the study.

Radiological assessments for all patients were performed prior to the first dose to establish a baseline, and every 6 weeks thereafter to evaluate disease progression as defined by RECIST criteria (v1.1). The RECIST criteria are unified, easily applicable criteria for measuring tumour response in Computed Tomography (CT) and Magnetic Resonance Imaging (MRI). Patients assigned a status of Progressive Disease following an assessment were withdrawn from the study. Patients assigned a status of Stable Disease or better were allowed to continue.

At least one patient in each of the four cohorts dosed had a radiological assessment of Stable Disease. Duration of treatment increased with each dose escalation up to Cohort 3 and dosing in Cohort 4 remains ongoing. One patient in Cohort 3 was dosed for 6 cycles without disease progression. None of the patients treated to date have had a partial or complete response as defined by RECIST v1.1 definition.

"We sincerely thank all of the Investigators who participated in this review. Their contribution to this process and their commitment to this ongoing study is invaluable, and this review will help us greatly in designing further studies for the continued development of this important drug candidate for Helix", stated Rob Verhagen, CEO of Helix BioPharma Corp. With no safety concerns to date and with enrollment on target, we expect to complete the enrollment of the Phase I component of this study by the summer 2014."

L-DOS47 is Helix's first immunoconjugate-based drug candidate in development based upon the Company's novel DOS47 technology, which is designed to use an innovative approach to modify the microenvironmental conditions of cancer cells in a manner that leads to their destruction. L-DOS47 is currently being clinically evaluated as a treatment for certain patients with NSCLC.

About the Clinical Study

The Phase I/II clinical study is an open-label study to evaluate the safety, tolerability and preliminary efficacy of ascending doses of L-DOS47, initially as a monotherapy, in patients with inoperable, locally advanced, recurrent or metastatic, non-squamous, stage IIIb/IV NSCLC. The study commenced with a starting dose of 0.12 micrograms of L-DOS47 per kilogram of patient body weight in the first patient cohort.

The total number of patients to be enrolled in the study will ultimately depend on how many ascending dose levels are required to reach the maximum tolerated dose (MTD); however, the Company currently anticipates that the study will enroll less than the estimated maximum of 48 patients in Phase I, as previously reported. Helix expects that twenty patients will be enrolled in the Phase II portion of the study at the MTD dose determined in Phase I. Study patients will be male or female, at least 18 years of age, with histologically confirmed non-small cell lung cancer. Patients will have an Eastern Cooperative Oncology Group ("ECOG") performance status of 0 - 2 at the screening visit for this study, and will have at least one site of measurable disease per RECIST v1.1.

The study is currently being conducted at four Polish centres; The Maria Sklodowska-Curie Memorial Cancer Centre & Institute of Oncology, The Military Medical Institute, The National Tuberculosis and Lung Diseases Research Institute and The Mazovian Centre of Pulmonary Diseases and Tuberculosis. As previously reported, the Company is actively recruiting new centers to participate in order to expand this study.

About Helix BioPharma Corp.

Helix BioPharma Corp. is a biopharmaceutical company specializing in the field of cancer therapy. The company is actively developing innovative products for the prevention and treatment of cancer based on its proprietary technologies. Helix's product development initiatives include its novel L-DOS47 new drug candidate and its Topical Interferon Alpha-2b. Helix is currently listed on the TSX and FSE under the symbol "HBP".

Forward-Looking Statements and Risks and Uncertainties

This news release contains certain forward-looking statements and information (collectively, "forward-looking statements") within the meaning of applicable Canadian securities laws, including, without limitation, those relating to the total number of patients to be enrolled in the Polish Phase I/II clinical study, the anticipated timelines for completion of such enrolment, the conduct of a further, formal analysis of available data. Forward-looking statements, which may be identified by words including, without limitation, "will", "may", "anticipates", "expects", and other similar expressions, are intended to provide information about management's current plans and expectations regarding the conduct of the clinical study.

Although Helix believes that the expectations reflected in such forward-looking statements are reasonable, such statements involve risks and uncertainties that may cause actual results or events to differ materially from those anticipated and no assurance can be given that these expectations will be realized, and undue reliance should not be placed on such statements. Risk factors that could cause actual results or events to differ materially from the forward-looking statements include, without limitation, (i) the inherent uncertainty involved in scientific research and drug development; (ii) the risks associated with delay or inability to complete clinical trials successfully, including that patient recruitment and continuing enrolment for the Polish Phase I/II clinical trial for L-DOS47 does not continue as scheduled or at all, and the long lead-times and high costs associated with obtaining regulatory approval to market any product which may result from successful completion of such trials; (iii) need to secure additional financing on terms satisfactory to Helix or at all; (iv) clinical trials that yield negative results, or results that do not justify future clinical development, including the risk that the Polish Phase I/II clinical trial for L-DOS47 will yield negative results; (v) the risk that additional centres satisfactory to Helix may not be identified in a timely manner or at all and that such additional centres, if opened, may not accelerate the anticipated timeline for the Polish Phase I/II clinical trial for L-DOS 47; and (v) those risks and uncertainties affecting the company as more fully described in Helix's most recent Annual Report, including under the headings "Forward-Looking Statements" and "Risk Factors", filed with the Canadian Securities Administrators at www.sedar.com (together, the "Helix Risk Factors"). Certain material factors or assumptions are applied in making the forward-looking statements, including, without limitation, that the opening of the additional centers will not negatively affect the management, operations or timelines associated with Helix's Polish Phase I/II clinical trial for L-DOS47 and that the Helix Risk Factors will not cause Helix's actual results or events to differ materially from the forward-looking statements.

Forward-looking statements and information are based on the beliefs, assumptions and expectations of Helix's management on the date of this news release, and Helix does not assume any obligation to update any forward-looking statement or information should those beliefs, assumptions or expectations, or other circumstances change, except as required by law.