DOR BioPharma Announces Initiation of Second Human Clinical Trial for RiVaxTM, Its Ricin Toxin Vaccine

EWING, NJ–(EMWNews – August 7, 2008) – DOR BioPharma, Inc. (OTCBB: DORB) (“DOR” or the

“Company”), a late-stage biopharmaceutical company, announced today that

one of its academic development partners has initiated a second human

clinical trial of RiVax™ in healthy volunteers. RiVax™ is a recombinant

subunit vaccine designed to induce protection against exposure to ricin

toxin, a category B biothreat. This new trial is intended to evaluate the

safety and immunogenicity of an improved formulation of the vaccine

containing an adjuvant that is expected to result in long lasting and high

levels of protective antibodies. The new trial is being conducted as part

of a program funded by a grant from the Orphan Products Division of the FDA

(“Food and Drug Administration”). Dr. Ellen Vitetta, Director of the

University of Texas Southwestern Medical Center’s Cancer Immunobiology

Center, is the Principal Investigator of the study.

DOR is presently conducting manufacturing and characterization of the new

RiVax™ formulation according to the FDA’s current good manufacturing

practices (“cGMPs”), anticipating that it will match requirements for

stockpiled vaccines predicted from current stability results and

pre-clinical efficacy results in animals. RiVax™ has already been

evaluated in a Phase I clinical trial to test the safety and immunogenicity

of the subunit lacking an adjuvant. Those results demonstrated that the

adjuvant-free RiVax™ was well tolerated and induced antibodies in humans

that neutralized ricin toxin in tissue culture and in mice. Serum

antibodies that neutralize ricin are expected to function to reduce

mortality and morbidity from exposure to ricin, even if exposure to ricin

is through aerosolization. The new formulation employs an adjuvant that is

very well characterized and used in many vaccines to induce protective,

neutralizing antibodies in humans. The new trial employs an escalating

dose strategy in which volunteers receive three intramuscular doses of

vaccine at six-week intervals, matching many commonly employed vaccination

regimens. The trial is designed to confirm that, in conjunction with the

adjuvant, the vaccine is safe at doses that induce protective antibodies,

and that an adjuvanted formulation results in sustained and higher titer

antibodies. Safety and immunogenicity data is anticipated in the first half

of 2009.

“From the vaccine dose levels being evaluated in this trial, we hope to

establish a dose for Phase 2 human trials,” said Dr. Vitetta.

“We have been encouraged by the safety and animal efficacy results to date,

and combined with our accruing stability data, we are poised to carry out

expanded Phase 2 human trials in the next six to nine months,” said Dr.

Robert N. Brey, Ph.D., Chief Scientific Officer of DOR. “This adjuvanted

formulation will further guide us in determination of safety and efficacy.

In conjunction with results from our ongoing non-human primate trial, it

will aid in elucidating correlation between the antibody levels in humans

and protection from aerosolized toxin in non-human primates.”

About Ricin Toxin

Ricin toxin is a potent plant toxin that can be easily produced from

abundantly available castor beans. Ricin enters cells and enzymatically

inhibits protein synthesis leading to cell death and generation of an

irreversible inflammatory response. General organ failure leading to death

can occur within several days of exposure. Ricin is highly toxic to humans

and other mammals because it has the ability to enter virtually any type of

cell and affect any organ in the body. Exposure to small amounts,

especially by inhalation, leads to lung damage, nausea, fever, and

abdominal pain, and death within several days. Diagnosis of ricin poisoning

is difficult since the symptoms resemble those of other illnesses. There

are no known effective antidotes for ricin exposure. The potential use of

ricin toxin as a biological weapon of mass destruction has been highlighted

in a recent FBI Bioterror report released last November entitled Terrorism

2002-2005 which states that “Ricin and the bacterial agent anthrax are

emerging as the most prevalent agents involved in WMD investigations”

(http://www.fbi.gov/publications/terror/terrorism2002_2005.pdf). Ricin

toxin is thought to be a bioterror threat because of its stability and high

potency as well as the large worldwide reservoir created as a by-product of

castor oil production. It is second only to botulinum toxin as the most

lethal natural toxin. The need for protective countermeasures against ricin

toxin has been emphasized by its recent and continued use as a biological

weapon. The successful development of an effective vaccine against ricin

toxin may act as a deterrent against the actual use of ricin as a

biological weapon and could be used in rapid deployment scenarios in the

event of a biological attack.

About RiVax™

There are currently no vaccines available to prevent ricin poisoning or

medical treatments to care for poisoning victims. RiVax™ was developed

after the discovery that two key sites in the enzymatically active A chain

of ricin toxin can be simultaneously altered to eliminate toxicity. After

eliminating toxicity, the inactive ricin A chain induces antibodies in

animals that recognize and neutralize the intact toxin. A vaccine is

considered by many to be the best way to prospectively protect populations

at risk of exposure against ricin toxin. RiVax™ is a subunit vaccine

based on the purified and genetically inactivated A chain of ricin toxin.

This vaccine would potentially be added to the Strategic National Stockpile

and dispensed in the event of a terrorist attack.

The program is being funded by grants from NIAID, which have totaled over

$11 million in direct funding to DOR. NIAID also awarded a $2.6 million

grant to UT Southwestern for animal model development and the FDA Orphan

Products Grants Program has funded ~$1 M for the conduct of the current

clinical trial, supporting clinical supply and vaccine characterization.

About DOR BioPharma, Inc.

DOR BioPharma, Inc. (DOR) is a late-stage biopharmaceutical company

developing products to treat life-threatening side effects of cancer

treatments and serious gastrointestinal diseases, and vaccines for certain

bioterrorism agents. DOR’s lead product, orBec® (oral beclomethasone

dipropionate or BDP), is a potent, locally acting corticosteroid being

developed for the treatment of gastrointestinal Graft-versus-Host disease

(GI GVHD), a common and potentially life-threatening complication of bone

marrow transplantation. DOR filed a New Drug Application for orBec® with

the FDA for the treatment of acute GI GVHD and received a not approvable

letter in which the FDA has requested data from a confirmatory Phase 3

clinical trial to demonstrate the safety and efficacy of orBec®.

orBec® is currently the subject of an NIH-supported, Phase 2, randomized,

double-blind, placebo-controlled trial in the prevention of acute GVHD.

Oral BDP may also have application in treating other gastrointestinal

disorders characterized by severe inflammation. DOR has initiated a

development program with its Lipid Polymer Micelle (LPM™) drug delivery

technology for the oral delivery of leuprolide for the treatment of

prostate cancer and endometriosis.

Through its Biodefense Division, DOR is developing biomedical

countermeasures pursuant to the Project BioShield Act of 2004. DOR’s

biodefense products in development are recombinant subunit vaccines

designed to protect against the lethal effects of exposure to ricin toxin,

botulinum toxin and anthrax. DOR’s ricin toxin vaccine, RiVax™, has been

shown to be well tolerated and immunogenic in a Phase 1 clinical trial in

normal volunteers.

For further information regarding DOR BioPharma, Inc., please visit the

Company’s website located at www.dorbiopharma.com.

This press release contains forward-looking statements, within the meaning

of Section 21E of the Securities Exchange Act of 1934, that reflect DOR

BioPharma, Inc.’s current expectations about its future results,

performance, prospects and opportunities, including statements regarding

the potential use of orBec® for the treatment of gastrointestinal GVHD

and the prospects for regulatory filings for orBec®. Where possible, DOR

has tried to identify these forward-looking statements by using words such

as “anticipates,” “believes,” “intends,” or similar expressions. These

statements are subject to a number of risks, uncertainties and other

factors that could cause actual events or results in future periods to

differ materially from what is expressed in, or implied by, these

statements. DOR cannot assure you that it will be able to successfully

develop or commercialize products based on its technology, including

orBec®, particularly in light of the significant uncertainty inherent in

developing vaccines against bioterror threats, manufacturing and conducting

preclinical and clinical trials of vaccines, and obtaining regulatory

approvals, that its technologies will prove to be safe and effective, that

its cash expenditures will not exceed projected levels, that it will be

able to obtain future financing or funds when needed, that product

development and commercialization efforts will not be reduced or

discontinued due to difficulties or delays in clinical trials or due to

lack of progress or positive results from research and development efforts,

that it will be able to successfully obtain any further grants and awards,

maintain its existing grants which are subject to performance, enter into

any biodefense procurement contracts with the US Government or other

countries, enter into a definitive agreement with IDIS for a NPAP for

orBec® for the treatment of GI GVHD, that the US Congress may not pass

any legislation that would provide additional funding for the Project

BioShield program, that it will be able to patent, register or protect its

technology from challenge and products from competition or maintain or

expand its license agreements with its current licensors, or that its

business strategy will be successful. Important factors which may affect

the future use of orBec® for gastrointestinal GVHD include the risks

that: the FDA’s requirement that DOR conduct additional clinical trials to

demonstrate the safety and efficacy of orBec® will take a significant

amount of time and money to complete and positive results leading to

regulatory approval cannot be assumed; DOR is dependent on the expertise,

effort, priorities and contractual obligations of third parties in the

clinical trials, manufacturing, marketing, sales and distribution of its

products; orBec® may not gain market acceptance if it is eventually

approved by the FDA; and others may develop technologies or products

superior to orBec®. These and other factors are described from time to

time in filings with the Securities and Exchange Commission, including, but

not limited to, DOR’s most recent reports on Form 10-QSB and Form 10-KSB.

DOR assumes no obligation to update or revise any forward-looking

statements as a result of new information, future events, and changes in

circumstances or for any other reason.

Company Contact: Evan Myrianthopoulos Chief Financial Officer (609) 538-8200 www.dorbiopharma.com