EXHIBIT 99.1

|Contact Information:                                                                                                                  |  |                                                                                                                         
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|Ribozyme Pharmaceuticals, Inc.2950 Wilderness Place
Boulder, CO 80301
(303) 449-6500
Cathy Robins, Director, Corporate Communications |  | CCG, Public/Investor Relations15300 Ventura Blvd., Suite 303
Sherman Oaks, CA 91403
(818) 789-0100
Sean Collins, Partner

RIBOZYME PHARMACEUTICALS ANNOUNCES
CLINICAL TRIALS UPDATE AND CONFERENCE CALL

| |  | Conference Call Information
Date: April 30, 2002
Time: 11:00 am EDT
Dial-In Number: (800) 388-8975
Reference: RPI Clinical Trials Update
Webcast segment available atwww.rpi.com. |  | 
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BOULDER,
Colorado, April 30, 2002Ribozyme Pharmaceuticals, Inc. ("RPI," NASDAQ: RZYM) today announced an update on its Phase II clinical trials status for
ANGIOZYME®, and HEPTAZYME, and its Phase I clinical trial for HERZYME. This clinical trial update will give important information regarding clinical progress
achieved in the development of ribozymes for therapeutic application. According to Howard W. Robin, President and Chief Executive Officer of RPI, "We believe RPI has made encouraging advances in
demonstrating the utility of ribozymes as a new class of therapeutic agents and felt it would be appropriate to provide a thorough update on the status of our clinical trial work."

RPI's
lead drug candidate, ANGIOZYME, is partnered with Chiron Corporation and is being evaluated as an angiogenesis inhibitor in two separate Phase II clinical trials for which
enrollment has been completed: (i) as a monotherapy for metastatic breast cancer, where positive biological activity has been observed, and (ii) as a combination therapy in conjunction
with the Saltz regimen for metastatic colorectal cancer, where results to date have been encouraging. HEPTAZYME is a ribozyme developed to prevent replication of the hepatitis C virus, and our Phase
II clinical trial has demonstrated a reduction in serum HCV RNA levels in 10% of patients on trial; however, we recently stopped dosing in this trial to review an animal toxicity issue. HERZYME, which
is being developed in partnership with Elan Corpration plc, is in a Phase I trial for patients with HER2 over-expressing breast cancer.

Mr. Robin
stated "We are pleased to announce the first demonstration of ribozyme biologic activity in humans. This important achievement is a key step in the transition of
ribozymes from laboratory science to therapeutics. While challenges remain, we are excited about continuing to develop this potentially important new class of compounds."

ANGIOZYME

Metastatic Breast Cancer Trial Enrollment Completed

RPI has completed enrollment of 45 patients in the Phase II open-label ANGIOZYME trial. This study was designed to evaluate the drug's potential
anti-cancer activity as monotherapy for patients with stage IV metastatic breast cancer. ANGIOZYME is a ribozyme that targets the high affinity receptor for Vascular Endothelial Growth
Factor (VEGFR-1) and is designed to decrease the growth of new blood vessels to tumors, thus preventing the growth and metastasis of cancer.

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Positive Biological Activity DemonstratedMonotherapy Response Not Achieved

In the Phase II metastatic breast cancer trial, treatment with ANGIOZYME has resulted in a statistically significant reduction in the levels of soluble
VEGFR-1. The trial demonstrates that ANGIOZYME has specific biological activity in patients with stage IV metastatic breast cancer, which is one of the objectives this trial sought to
verify. Although this important endpoint was achieved, ANGIOZYME as a monotherapy did not achieve a clinically meaningful response rate.

According
to Gabriel Hortobagyi, MD, Professor and Chairman, Department of Breast Medical Oncology, MD Anderson Cancer Center and Principal Investigator for the breast cancer trial, "We
were very pleased by the safety profile of ANGIOZYME. Given what we have recently learned in the field of anti-angiogenics, we now do not expect to see clinically relevant responses for
anti-angiogenics when used as monotherapies. Therefore, clinical studies of anti-angiogenic agents now utilize combination therapies to effect tumor growth by multiple
mechanisms. We are, however, very pleased that we have met one of the important study endpoints namely, a reduction in soluble VEGFR-1 levels. These results indicate that ANGIOZYME is a
biologically active agent. We look forward to undertaking additional trials with ANGIOZYME in combination with other agents in patients with breast cancer."

Combination Therapy Colorectal Trial Enrollment Completed

The ANGIOZYME Phase II metastatic colorectal trial has completed enrollment. Eligible patients in this trial receive ANGIOZYME in combination with the standard
chemotherapy regimen of CPT-11, 5-FU and leucovorin (i.e. the Saltz regimen). The trial began in June 2001 and final 12 week response rate results are expected by
year-end 2002.

Alan
Venook, MD, Professor of Clinical Medicine, Chief of Gastrointestinal Oncology at University of California San Francisco and Principal Investigator of the ANGIOZYME colorectal
combination study states, "We are very pleased that the trial enrollment was completed within such a short timeframe. To date, the results are encouraging and we look forward to analyzing the data at
the end of this year."

HEPTAZYME

Reduces Serum HCV RNA Levels In Chronic Hepatitis C Patients

The Phase II HEPTAZYME clinical trial is an open-label study designed to evaluate the safety and efficacy of HEPTAZYME alone and in combination with
interferon. In the 100 mg/m2 BID cohort, where HEPTAZYME was administered as monotherapy, a biologically meaningful reduction in serum HCV RNA levels was demonstrated in 10% of patients.
These results are favorable in comparison to trials of ribavirin monotherapy which is now used in combination with type 1 interferon as the standard of care for treatment of chronic hepatitis C.

According
to Dr. Myron Tong, Professor of Medicine, USC, and Chief of the Liver Center, Huntington Memorial Hospital, and HEPTAZYME Principal Investigator, "We are extremely
encouraged by these initial HEPTAZYME monotherapy results and we are excited about studying this important new agent in combination with type 1 interferon. Given that HEPTAZYME has a novel mode of
action, it has the potential to be combined not only with interferon, but with other anti-viral approaches to hepatitis C. There remains a great unfilled need for improved therapies to
treat chronic hepatitis C and we are hopeful that HEPTAZYME will fill this void."

RPI Stops Dosing to Resolve Animal Toxicity Question

After recent discussions with the FDA, RPI has stopped dosing in the HEPTAZYME Phase II trial in order to review the observation of loss of vision in one animal.
This observation was noted in the final month of a twelve-month chronic toxicology study conducted at three times the anticipated maximum dosing levels in humans. The correlation of this finding in
one animal to HEPTAZYME exposure has not been determined. RPI is evaluating additional animal toxicology data to determine

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the significance of this event. The enrollment of the planned third cohort of patients in combination with interferon is anticipated to occur following review of this additional data by RPI and the
FDA. When completed, the Phase II trial enrollment will include a total of over 70 patients.

According
to Willis Maddrey, MD, Professor of Medicine, University of Texas Southwestern Medical Center, Chairman of the HEPTAZYME Drug Safety and Monitoring Board, "I've been involved
in the study of hepatitis C research since the discovery of this insidious virus and I'm encouraged by the initial results shown by HEPTAZYME in several patients in this clinical trial. We are
concerned about the observation of loss of vision in one animal, but, the relationship between the loss of vision in the animal and HEPTAZYME dosing is unknown. RPI is acting responsibly by stopping
the dosing until the toxicology question is answered."

HERZYME

The Phase I dose-escalation study in patients with HER2 over-expressing cancers is in progress at the British Columbia Cancer Agency
(BCCA). This trial is being supported by the business venture set up by Elan and RPI, Medizyme Pharmaceuticals. In this study HERZYME is being delivered sub-cutaneously using Elan's
Medipad® device. The Principal Investigator is Dr. Karen Gelmon, Professor of Medicine, University of British Columbia and Head, Investigational Drug Program, Advanced Therapeutics,
Department of Medical Oncology, BCCA. Enrollment in this trial is proceeding as expected, currently enrolling the third dose cohort. Preliminary results are expected later this year.

In
conclusion, Mr. Robin stated "Our clinical trials suggest that ribozymes have significant human activity as demonstrated by the biological marker activity in the ANGIOZYME
breast cancer study and the viral reduction activity in the HEPTAZYME trial. In addition, we are encouraged by the results observed thus far in the Phase II metastatic colorectal combination trial for
ANGIOZYME."

About Ribozyme Pharmaceuticals

RPI, atwww.rpi.com, is a global leader in the development of ribozyme-based biotherapeutics and diagnostic tools
for the treatment and monitoring of significant human diseases. Ribozymes are the product of Nobel Prize-winning research and are synthetically engineered to act as "molecular scissors" capable of
cleaving target RNA in a highly specific manner, blocking gene expression and preventing production of unwanted proteins. In addition to its therapeutic and diagnostic pipeline, RPI is leveraging its
broad-based nucleic acid technology for applications in genomics, proteomics, and individualized therapeutics. To date, RPI has spun out and licensed technology to atugen AG which is focused on target
validation and additionally earlier this year announced a licensing agreement with Archemix, Inc. for the use of allosteric ribozymes in drug discovery and optimization and environmental
monitoring. RPI holds equity positions in both companies and retains certain residual rights. RPI is currently engaged in negotiations with third parties concerning other possible strategic alliances.

RPI's
anti-hepatitis C virus ribozyme, HEPTAZYME, is in Phase II clinical development in a multi-center trial in the U.S. RPI is partnered with Chiron
Corporation for the development and commercialization of ANGIOZYME®, an anti-angiogenic ribozyme designed to inhibit the growth of new vasculature to supply blood to tumors and
prevent tumor growth and metastasis, which is also in two Phase II clinical trials. Other RPI development projects include, HERZYME, an anti-HER2 ribozyme for treatment of
breast and other cancers in Phase I development and HepBzyme, a ribozyme for the treatment of hepatitis B. The HERZYME program is being developed by an RPI/Elan business venture, Medizyme
Pharmaceuticals Ltd. In addition, RPI is collaborating with Geron Corporation utilizing the expertise of each company to accelerate process development for Geron's lead telomerase inhibitor,
GRN163. RPI also entered into an agreement with Fujirebio, Inc., the largest domestic diagnostic company in Japan, to develop and commercialize ribozyme-based clinical diagnostic products.

ANGIOZYME®
is a registered trademark of Ribozyme Pharmaceuticals Inc. HEPTAZYME, HERZYME and HepBzyme are trademarks of Ribozyme
Pharmaceuticals Inc.

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This press release contains forward-looking statements that involve risks and uncertainties, and actual events or results may differ materially. These risk
factors include actions by the U.S. Food and Drug Administration, technological advances, ability to obtain rights to technology, ability to obtain and enforce patents, ability to commercialize and
manufacture products and general economic conditions. These and additional risk factors are identified in the Company's Securities and Exchange Commission filings, including the Forms 10-K
and 10-Q and in other SEC filings.

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