Mucosal Improvement Observed in 61% of the Patients and 33% achieved Mucosal Healing
Clinical Responses Observed in 67% of the Patients
and Clinical Remission Observed in 28% of the Patients
89% of the Patients Experienced a Reduction in Mayo Score, and 61% of the Patients
Experienced a Reduction in Endoscopic Sub Score
No Systemic Absorption Observed
CARMIEL, Israel, June 05, 2018 (GLOBE NEWSWIRE) -- Protalix BioTherapeutics, Inc. (NYSE American:PLX) (TASE:PLX), announced
today that additional positive results from the Company’s phase II clinical trial of OPRX-106 for the treatment of ulcerative
colitis (UC) were presented at the Digestive Disease Week® (DDW) 2018 Annual Meeting. OPRX-106 is a plant cell-expressed
recombinant human tumor necrosis factor receptor II fused to an IgG1 Fc domain (TNFRII-Fc), in development for oral administration.
When administered orally and passing through the digestive tract, the plant cells function as a natural delivery vehicle.
The unique attribute of a cellulose plant cell wall provides resistance to degradation as opposed to proteins produced via
mammalian cell expression. The Digestive Disease Week® (DDW) 2018 Annual Meeting is taking place in Washington, D.C., June
2-5, 2018.
The phase II clinical trial is a randomized, open label, 2-arm study of OPRX-106 for the treatment of ulcerative colitis
(UC). A total of 24 patients were enrolled in the study, 18 patients completed the study with 6 patients who did not complete
the study. The dropout rate is consistent with other trials in similar patient populations, and none of the patients dropped
out due to a side effect or serious adverse event. Patients were randomized to receive 2 mg or 8 mg of OPRX-106, administered
orally, once daily, for 8 weeks. The average baseline Mayo score was 7.1 (from a scale of 0-12) and the average baseline
mucosal endoscopy sub score was 2.1 (from a scale of 0-3). For the 18 patients who completed the study, 89% had a baseline
Mayo score between 6 and 9, which meets the criteria of moderate disease activity, and 84% had a baseline mucosal endoscopy sub
score of 2 and above indicating moderate to severe disease based on mucosal appearance.
The key efficacy endpoints of the study were met at week 8:
- 67% of patients experienced a clinical response in each of the 2mg dose and 8mg dose cohorts;
- 44% of patients experienced a clinical remission in the 8mg dose and 11% in the 2mg dose for an overall average of 28%.
Clinical response at week 8 is defined as a decrease in the Mayo score of at least 3 points and either a decrease in the
sub-score for rectal bleeding of at least 1 point from baseline, or rectal bleeding sub-score of 0 or 1. Clinical remission
at week 8 is defined as clinically symptom free, a Mayo score ≤ 2, with no individual sub-score exceeding 1 point after
treatment.
In addition to clinical response and remission, efficacy was also observed in mucosal healing, an important prognostic parameter
in ulcerative colitis and other inflammatory bowel diseases, measured by endoscopy:
- 61% of patients experienced mucosal improvement; and
- 33% of patients experienced mucosal healing.
Mucosal improvement is defined as a decrease in endoscopy sub-score at week 8. Mucosal healing is defined as a reduction
in, and achievement of, endoscopy sub-score ≤1 at week 8.
Other key efficacy endpoints were also achieved, as follows:
- 72% of patients showed an improvement in rectal bleeding scores;
- 72% of patients demonstrated an improvement in fecal calprotectin; and
- 61% of patients showed improved Geboes score (a histopathological scoring for the assessment of disease activity in
ulcerative colitis).
The positive trend in efficacy is consistent in substantially all patients. This trend is demonstrated by 89% of the
patients having showed an improvement in Mayo score in both doses, with an average decrease in Mayo score of 46% at week 8 in the
8mg dose and 40% in the 2mg dose. In addition, all of the patients also showed an improvement in at least one of the other
efficacy parameters.
No anti-drug antibodies were detected. In addition, no systemic absorption was observed. OPRX-106 was safe and well
tolerated with only mild to moderate adverse events, which were transient in nature. Headaches were the most common adverse
event reported.
“The full set of data from the study is very compelling, and suggests that OPRX-106 is an effective anti-inflammatory agent.
OPRX-106 is delivered orally and is biologically active in the gut without triggering the formation of anti-drug or systemic
absorption. OPRX-106 has the potential to address the loss of response and to avoid critical safety concerns of infections
and malignancies currently seen in anti–TNF alpha treatment, which is driven by the high presence of neutralizing antibodies and
systemic absorption respectively,” said Professor Yaron Ilan, Chairman of the Department of Medicine, and an expert in
Gastroenterology, at The Hadassah Hebrew University Medical Center in Jerusalem, and a consultant to the Company. “I am
looking forward to participating in additional trials of OPRX-106 and to continue to see this program progress as it offers new
hope for patients with ulcerative colitis by addressing significant unmet medical needs of patients.”
“We are very pleased by these excellent results, particularly with respect to the significant percent of patients demonstrating
mucosal healing and clinical remission at eight weeks,” commented Moshe Manor, Protalix’s President and Chief Executive
Officer. “OPRX-106 may bring a new therapy paradigm in the ulcerative colitis space potentially offering better safety,
longer term efficacy and oral administration in place of most therapies which are administered via injection and infusion and bear
serious safety concerns.”
The presentation made at the DDW 2018 Annual Meeting is available on the Company’s website.
About Protalix BioTherapeutics, Inc.
Protalix is a biopharmaceutical company focused on the development and commercialization of recombinant therapeutic proteins
expressed through its proprietary plant cell-based expression system, ProCellEx®. Protalix’s unique expression system
presents a proprietary method for developing recombinant proteins in a cost-effective, industrial-scale manner. Protalix’s
first product manufactured by ProCellEx, taliglucerase alfa, was approved for marketing by the U.S. Food and Drug
Administration (FDA) in May 2012 and, subsequently, by the regulatory authorities of other countries. Protalix has licensed
to Pfizer Inc. the worldwide development and commercialization rights for taliglucerase alfa, excluding Brazil, where Protalix
retains full rights. Protalix’s development pipeline includes the following product candidates: pegunigalsidase alfa, a
modified version of the recombinant human alpha-GAL-A protein for the treatment of Fabry disease; OPRX-106, an orally-delivered
anti-inflammatory treatment; alidornase alfa for the treatment of Cystic Fibrosis; and others. Protalix has entered into an
ex-United States partnership with Chiesi Farmaceutici S.p.A. for the development and commercialization of pegunigalsidase
alfa. Protalix maintains full rights to pegunigalsidase alfa in the United States.
Forward-Looking Statements
To the extent that statements in this press release are not strictly historical, all such statements are forward-looking, and
are made pursuant to the safe-harbor provisions of the Private Securities Litigation Reform Act of 1995. The terms
“anticipate,” “believe,” “estimate,” “expect,” “plan” and “intend” and other words or phrases of similar import are intended to
identify forward-looking statements. These forward-looking statements are subject to known and unknown risks and
uncertainties that may cause actual future experience and results to differ materially from the statements made. These
statements are based on our current beliefs and expectations as to such future outcomes. Drug discovery and development
involve a high degree of risk. Factors that might cause material differences include, among others: failure or delay in the
commencement or completion of our preclinical and clinical trials which may be caused by several factors, including: slower than
expected rates of patient recruitment; unforeseen safety issues; determination of dosing issues; lack of effectiveness during
clinical trials; inability to monitor patients adequately during or after treatment; inability or unwillingness of medical
investigators and institutional review boards to follow our clinical protocols; and lack of sufficient funding to finance clinical
trials; the risk that the results of the clinical trials of our product candidates will not support our claims of superiority,
safety or efficacy, that our product candidates will not have the desired effects or will be associated with undesirable side
effects or other unexpected characteristics; risks related to the amount and sufficiency of our cash and cash equivalents; risks
related to the amount of our future revenues, operations and expenditures; risks relating to our ability to make scheduled payments
of the principal of, to pay interest on or to refinance our outstanding notes or any other indebtedness; our dependence on
performance by third party providers of services and supplies, including without limitation, clinical trial services; the inherent
risks and uncertainties in developing drug platforms and products of the type we are developing; the impact of development of
competing therapies and/or technologies by other companies and institutions; potential product liability risks, and risks of
securing adequate levels of product liability and other necessary insurance coverage; and other factors described in our filings
with the U.S. Securities and Exchange Commission. The statements in this press release are valid only as of the date hereof
and we disclaim any obligation to update this information, except as may be required by law.
Investor Contact
Marcy Nanus
Solebury Trout Group
646-378-2927
mnanus@troutgroup.com
