Protalex Announces Data from Phase 1b Trial of PRTX-100 in Patients with Immune Thrombocytopenia Presented at the European Hematology Association 23rd Annual Meeting

Protalex, Inc. (OTCQB: PRTX), a clinical-stage biopharmaceutical
company, today announced that data highlighting results from its
European Phase 1b open-label, dose-escalation study of PRTX-100 in adult
patients with persistent/chronic immune thrombocytopenia (ITP) (the
PRTX-100-203 Study) were presented in a poster today at the European
Hematology Association 23rd Annual Meeting underway in
Stockholm. Protalex’s lead drug candidate PRTX-100, is a highly purified
form of staphylococcal protein A. The poster is now available on the
Company’s website at www.protalex.com.

The poster, entitled “A Phase 1B Open-Label Dose-Escalation Study of
PRTX-100, a Highly Purified Form of Staphylococcal Protein A (SpA), in
Adult Patients with Persistent/Chronic Immune Thrombocytopenia,” was
presented by a principal investigator for the 203 Study, Dr. Nicola
Cooper, Hammersmith Hospital, London.

The poster highlights findings from fifteen patients enrolled in all
five dose escalating cohorts and included seven women and eight men ages
22 to 82. The primary objective of this study was to evaluate the safety
of five different doses of PRTX-100. The data demonstrated that PRTX-100
had an acceptable safety profile across the dose range studied. The data
also showed that platelet counts were elevated in most patients that
received four weeks of treatment, with six patients having a peak
platelet count that was at least double their baseline count. Two
patients achieved a per protocol platelet response. Enrollment in the
203 Study was completed in May and final data will be presented at a
future scientific conference following completion of analysis in the
next few months.

“We are pleased to present data demonstrating the safety and
tolerability of PRTX-100 in the target ITP patient population. The
increase in platelets observed in many patients is similarly positive
and this data will contribute to developing an advanced clinical trial
strategy,” stated Richard J. Francovitch, Ph.D., Protalex’s Vice
President, ITP Programs. “ITP is a debilitating illness that affects
patient quality of life and contributes to mortality if left untreated.
We believe that PRTX-100 may prove to be a safe and effective therapy in
the treatment of this disease.”

About the PRTX-100-203 Study

The 203 Study is a Phase 1b, open-label, dose-escalating study conducted
in Europe that enrolled fifteen patients in five separate dose cohorts.
Patients with chronic, persistent ITP were eligible for the 203 Study if
they had received one prior ITP treatment and their platelet counts
remained low. Each patient who completed the study received four weekly
intravenous doses of PRTX-100 and was monitored for up to 48 weeks
thereafter. The primary study endpoint of the 203 Study is to evaluate
the safety of PRTX-100. Secondary endpoints include efficacy,
immunogenicity, and pharmacokinetics.

About Immune Thrombocytopenia (ITP)

ITP is an autoimmune condition characterized by bruising and increased
bleeding due to immune-mediated accelerated destruction of platelets and
impaired production of platelets. The diagnosis of ITP is based upon a
low platelet count, usually less than 100,000 per microliter of blood,
in the absence of other possible causes of reduced platelet numbers such
as an underlying illness or medication.

About PRTX-100

PRTX-100, a new generation immunomodulatory therapy, is a highly
purified form of SpA, an immunomodulatory protein known to modify
aspects of the human immune system. PRTX-100 has the ability, at very
low concentrations, to bind to human B-lymphocytes and macrophages and
to modulate immune processes. Pre-clinical data indicate that PRTX-100
may have the potential to treat ITP by reducing the immune-mediated
destruction of the platelets. The two most recently approved drugs used
to treat ITP, Nplate® (romiplostin) and Promacta®/Revolade™
(eltrombopag) both increase the production of platelets but do not
appear to affect the underlying platelet destruction process. The
safety, tolerability, and pharmacokinetics of PRTX-100 have been
characterized in eight human clinical studies (seven completed, one
ongoing), and PRTX-100 has been granted Orphan Drug Designation in the
U.S. and Europe for the treatment of ITP. In two Phase 1b clinical
trials in adult patients with active Rheumatoid Arthritis (RA), PRTX-100
was generally safe and well tolerated at all dose levels, and at certain
higher doses, more patients showed improvement in measures of RA disease
activity than did patients at the lower dose or placebo cohorts.
PRTX-100 is given as a short intravenous infusion.

Nplate® is a registered trademark of Amgen, Inc. and Promacta®/Revolade™
are registered trademarks of Novartis AG.

About Protalex, Inc.

Protalex, Inc. is a clinical-stage biopharmaceutical company focused on
the development of a class of drugs for treating autoimmune and
inflammatory diseases including RA and ITP. In the U.S., Protalex has
open INDs for the treatment of RA and ITP and in Europe, an open IMPD
for ITP. Please visit the Protalex website at www.protalex.com
to learn more about Protalex and its lead drug candidate, PRTX-100.

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