XBiotech, Inc: XBiotech Announces Presentation of Data from Phase 2 Study Evaluating MABp1 for the Treatment of Hidradenitis Suppurativa

Data Presented at the 7th Conference of the European Hidradenitis Suppurativa
Foundation (EHSF) Provide Results that Corroborate HiSCR findings with iHS4
Scoring as a Measure of Efficacy 

AUSTIN, Texas, 2018-01-26 14:00 CET (GLOBE NEWSWIRE) --
XBiotech Inc. (NASDAQ:XBIT) announced today additional data analysis of its
Phase 2 study evaluating XBiotech's True Human antibody, MABp1, as a treatment
for Hidradenitis Suppurativa (HS). The study achieved its primary endpoint,
showing significant treatment benefit using the HiSCR endpoint, which is the
method used in the development of the only therapy currently approved for the
treatment of HS. However, other methods of evaluating disease severity and
response to treatment have been proposed.  The iHS4 scoring system has recently
been proposed as a new measure of HS disease severity 1 but its usefulness as a
clinical measure has not been extensively studied. Investigators used data from
the Phase 2 study to evaluate the iHS4 scoring method to see how it correlates
with the HiSCR findings. 

These findings will be presented at the European Hidradenitis Suppurativa
Foundation (EHSF) Conference occurring in Rotterdam Netherlands February 7-9th.
The poster presentation titled, "Validation of the iHS4 Score as an Outcome
Measure for Hidradenitis Suppurativa (HS): Application in Treatment with MABp1
Targeting Interleukin-1alpha" will be featured beginning at 10:00 am, on the
8th of February, 2018. 

The data presented are thus a retrospective analysis using the iHS4 score for
all 20 patients who were randomized to receive either placebo or MABp1 therapy
in the Phase 2 double-blind study. At least 30% decrease of the iHS4 score from
the baseline at week 12 was associated with 100% sensitivity for positive HiSCR
score (the efficacy measure used in the phase 2 study). This change was found
in one (10%) and in four (40%) patients allocated to placebo and MABp1,
respectively (p= 0.046). 

Theodora Kanni, M.D., Ph.D., Attikon University Hospital in Athens, Greece
where the study was conducted, commented, "We find these results intriguing as
we believe the consistent trend of the iHS4 and HiSCR scores for the Phase 2
data demonstrate its accuracy in measuring outcomes in HS patients. We look
forward to future use of this scoring as an additional measure of efficacy in
the clinic." Prof. Evangelos J. Giamarellos-Bourboulis, M.D., Ph.D., who was
the Principal Investigator and Co-coordinator for the study, also added, "The
decrease of the iHS4 score among patients treated with MABp1 is a further proof
of its efficacy in HS." 

Results of the Phase 2 study were recently published in the Journal of
Investigative Dermatology, reporting that the study met its primary endpoint
and demonstrated a significant improvement in HS patients treated with MABp1
compared to control after 12 weeks of therapy (Response rate of 60% vs 10%,
respectively (p=0.035)). The 20 patient double-blind, placebo-controlled study
was designed to evaluate the safety and efficacy of MABp1, the Company's True
Human antibody targeting interleukin-1 alpha (IL-1a), in patients with HS not
eligible for anti-TNF therapy. Patients were randomized 1:1 to receive either
MABp1 or placebo every 2 weeks for 12 weeks. Patients in the study underwent
primary assessment of efficacy using Hidradenitis Suppurativa Clinical Response
(HiSCR) scores at 12 weeks, continued by a follow up phase to assess time to
relapse after an additional 12 weeks without therapy. Efficacy measures
included assessment of HiSCR scores, a validated method for evaluating efficacy
in HS patients, as well as quality of life assessment and ultrasonographic
evaluation. 

About True Human Therapeutic Antibodies
Unlike previous generations of antibody therapies, XBiotech's True Human
antibodies are derived without modification from individuals who possess
natural immunity to certain diseases. With discovery and clinical programs
across multiple disease areas, XBiotech's True Human antibodies have the
potential to harness the body's natural immunity to fight disease with
increased safety, efficacy and tolerability. 

About XBiotech
XBiotech is a fully integrated global biosciences company dedicated to
pioneering the discovery, development and commercialization of therapeutic
antibodies based on its True Human proprietary technology. XBiotech currently
is advancing a robust pipeline of antibody therapies to redefine the standards
of care in oncology, inflammatory conditions and infectious diseases.
Headquartered in Austin, Texas, XBiotech also is leading the development of
innovative biotech manufacturing technologies designed to more rapidly,
cost-effectively and flexibly produce new therapies urgently needed by patients
worldwide. For more information, visit www.xbiotech.com. 

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1 Zouboulis CC, et al. Br J Dermatol 2017; 177: 1401.

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