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EXHIBIT 99.1
CONTACT: CONTACT:
Stacie D. Byars Michael Cimini and
Manager, Investor Relations John Blackwell
and Corporate Communications Investor and Media Relations
NeoRx Corporation Stern & Co.
(206) 286-2508 (212) 888-0044
NEORX UPDATES SKELETAL TARGETED RADIOTHERAPY (STR) PHASE I/II
TRIAL DATA--COMPLETE REMISSION RATES PROMISING; PHASE III TRIALS
AWAITING FDA RESPONSE--
SEATTLE, WA, December 4, 2000--NeoRx Corporation (Nasdaq: NERX) today announced
that Sergio Giralt, M.D., of MD Anderson Cancer Center (Houston, TX) and
co-principal investigator on the Company's phase I/II STR trial in multiple
myeloma, reported that 28 of 65 patients evaluated to date for efficacy on all
doses in the study were determined to be in complete remission. Three of these
28 patients were in complete remission when they entered the study and
maintained that status after treatment. Treatment consisted of escalating doses
of STR in combination with chemotherapy or chemotherapy plus total body
irradiation. These results were reported at the American Society of Hematology
meeting in San Francisco, CA. The Company cautions that results of phase I/II
trials may not predict the results of phase III trials.
"STR continues to show a very promising rate of complete remission in
this fatal disease," said Dr. Giralt. "The true benefit of STR will be
determined by the phase III trial comparing STR combined with melphalan
chemotherapy at a dose of 200mg/m(squared) to the same dose of melphalan
chemotherapy without STR."
Patients in the phase I/II study received escalating doses of STR in combination
with one of two high-dose therapies that have been reported to produce
equivalent rates of complete remission alone: melphalan chemotherapy at a dose
of 200mg/m(squared), or melphalan 140mg/m(squared) plus total body irradiation.
Excluding the 3 patients who entered the study in complete remission, 22 of 46
patients who received STR along with one of these high-dose therapies achieved
complete remission. Sixteen patients were treated with escalating doses of STR
in combination with melphalan 140mg/m(squared) without total body irradiation, a
lower dose transplant regimen; 3 of these 16 patients had complete remissions.
In the phase I/II trial two methods were used to calculate the average dose to
marrow. Using the more conservative calculation, some patients in the high dose
STR groups, therefore, received 40Gy and others received 48Gy. Of the 32
patients treated in these high-dose groups, 10 of 18 evaluated to date had
complete remission: 3 of 6 at the 40Gy dose and 7 of 12 at the 48Gy dose. The
Company's phase III trials use the more conservative method (40Gy) to calculate
average dose to marrow.
In a separate presentation at the meeting, Dr. Giralt also updated the safety
data from the phase I/II STR study. There have been 22 cases of damage to the
bladder wall observed to date. All of these cases occurred in patients who did
not have continuous bladder irrigation as part of their STR treatment. None of
the patients who had continuous bladder
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irrigation has shown bladder wall damage to date. All of NeoRx's current STR
protocols mandate continuous bladder irrigation.
Four patients who experienced damage to the bladder wall developed a serious
side effect, TTP/HUS (thrombotic thrombocytopenic purpura/hemolytic uremic
syndrome), approximately 6 to 9 months after treatment. TTP/HUS is a complex
syndrome with many potential triggering causes, and all four patients had at
least two known potential triggers of TTP/HUS. An independent Data Safety
Monitoring Board, established for NeoRx's STR phase III clinical trial in
multiple myeloma, investigated these cases and recommended proceeding with the
phase III study with modifications on monitoring and dose standardization. As
previously reported, NeoRx has suspended accrual and treatment on its STR trials
pending FDA review and receipt of FDA approval to proceed with the trials. The
Company is working cooperatively with the FDA to resolve the matter as soon as
possible.
For more information, please join the NeoRx Conference Call at 7:00 a.m. Pacific
// 10:00 a.m. Eastern on Wednesday, December 6, 2000. The call in number is
(800) 818-5264, confirmation number 460314 -- or -- listen via our live webcast
at www.vcall.com, or via our website at www.neorx.com. The conference call
replay number is (888) 203-1112, Confirmation number 460314 and will remain
available through December 15, 2000.
ABOUT NEORX
Seattle-based, NeoRx Corporation is developing innovative products designed to
provide improved treatments for patients with cancer.
This release contains forward-looking statements relating to the development of
the Company's products and future operating results that are subject to certain
risks and uncertainties that could cause actual results to differ materially
from those projected. The words "believe," "expect," "intend," "anticipate,"
variations of such words, and similar expressions identify forward-looking
statements, but their absence does not mean that the statement is not
forward-looking. These statements are not guarantees of future performance and
are subject to certain risks, uncertainties and assumptions that are difficult
to predict. Factors that could affect the Company's actual results include the
progress, costs and results of clinical trials, the availability, cost and
timely delivery of materials and services from third party suppliers and
collaborative partners, the satisfaction of regulatory requirements, and the
receipt, timing, terms and conditions of required regulatory approvals.
Reference is made to the Company's latest Quarterly Report on Form 10 - Q filed
with the Securities and Exchange Commission for a more detailed description of
such factors. Readers are cautioned not to place undue reliance on these
forward-looking statements that speak only as of the date of this release. The
Company undertakes no obligation to publicly update any forward-looking
statement to reflect new information, events or circumstances after the date of
this release or to reflect the occurrence of unanticipated events.
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Visit NeoRx at www.neorx.com. To receive NeoRx news releases via email, register
at www.neorx.com/news/pr.html.
NeoRx is a registered trademark of NeoRx Corporation in the United States and/or
foreign countries.
(c) 2000 NeoRx Corporation. All Rights Reserved.
