Nabi Biopharmaceuticals Effects Reverse Stock Split and Announces the Completion of and Final Exchange Ratio for the Business

Nabi Biopharmaceuticals Effects Reverse Stock Split and Announces the
Completion of and Final Exchange Ratio for the Business Combination
Transaction With Biota Holdings Limited

ROCKVILLE, Md., Nov. 9, 2012 (GLOBE NEWSWIRE) -- Nabi Biopharmaceuticals
(Nasdaq:NABI) announced today the effectiveness of its six-to-one reverse
stock split (the "Reverse Stock Split") of Nabi common stock, which became
effective as of 4:59 p.m., Eastern Standard Time, on November 8, 2012 (the
"Effective Time"). Nabi also announced today the closing of the business
combination transaction (the "Transaction") between Nabi and Biota Holdings
Limited (ASX:BTA.AX) (which occurred after the Effective Time) and a final,
split adjusted, exchange ratio of 0.1249539870 of a share of Nabi common stock
for each Biota ordinary share. In addition, Nabi's corporate name was changed
to Biota Pharmaceuticals, Inc. in connection with the closing of the
Transaction.Shares of common stock of the combined company, Biota
Pharmaceuticals, Inc., will begin trading on the NASDAQ Global Select Market
on a reverse split adjusted basis at the opening of trading on November 9,
2012 under a new CUSIP number under the new symbol "BOTA".

Upon the effectiveness of the Reverse Stock Split, every six shares of issued
and outstanding Nabi common stock were automatically combined into one issued
and outstanding share of Nabi common stock without any change in the par value
per share, rights and preferences of, or total number of authorized shares of
Nabi common stock. This reduced the number of issued and outstanding shares of
Nabi common stock from approximately 28.3 million to approximately
4.7million. Upon the closing of the Transaction, each Biota ordinary share
was transferred to Nabi in exchange for 0.1249539870 of a share of Nabi common
stock.Nabi issued an aggregate of approximately 23.4 million shares of Nabi
common stock to Biota stockholders in exchange for Biota ordinary
shares.Immediately after the closing of the Transaction, Biota
Pharmaceuticals, Inc. had approximately 28.1 million shares of common stock
outstanding.

In connection with the Reverse Stock Split, no fractional shares were issued.
Instead, each stockholder of record holding a fractional share as a result of
the Reverse Stock Split will receive a cash payment (without interest) in lieu
of the issuance of any such fractional share equal to (i) such fractional
share interest to which the stockholder would otherwise be entitled, after
taking into account all shares of Nabi common stock then held by the
stockholder immediately prior to the Effective Time, multiplied by (ii) the
average closing sale price of Nabi common stock for the 10 trading days
immediately prior to the Effective Time as officially reported by the NASDAQ
Global Select Market.

Based upon the Reverse Stock Split ratio of six-to-one, proportionate
adjustments were made to the per share exercise price and the number of shares
issuable upon the exercise of all outstanding stock options for Nabi common
stock. This resulted in approximately the same aggregate price being required
to be paid under such options upon exercise, and approximately the same value
of shares of Nabi common stock being delivered upon such exercise, immediately
following the Reverse Stock Split as was the case immediately preceding the
Reverse Stock Split. The number of shares deliverable upon settlement or
vesting of restricted stock awards were similarly adjusted. The number of
shares reserved for issuance pursuant to these securities was reduced
proportionately based upon the Reverse Stock Split ratio.

Nabi has retained its transfer agent, American Stock Transfer & Trust Company,
LLC ("AST"), to act as its exchange agent for the Reverse Stock Split. AST
will provide a letter of transmittal providing instructions for the exchange
of stock certificates to shareholders of record as of immediately prior to the
Effective Time. Stockholders owning shares via a broker or other nominee will
have their positions automatically adjusted to reflect the Reverse Stock
Split, subject to brokers' particular processes, and will not be required to
take any action in connection with the Reverse Stock Split.

Additional information regarding the Transaction and the effects of the
Reverse Stock Split may be found in Nabi's definitive proxy statement filed
with the Securities and Exchange Commission (the "SEC") on August7, 2012, as
supplemented by the supplement dated September25, 2012.

About Nabi Biopharmaceuticals

Nabi Biopharmaceuticals, headquartered in Rockville, Maryland, is a
biopharmaceutical company that has focused on the development of vaccines
addressing unmet medical needs, including nicotine addiction. Its sole product
currently in development is NicVAX® (Nicotine Conjugate Vaccine), an
innovative and proprietary investigational vaccine for the treatment of
nicotine addiction and prevention of smoking relapse based on patented
technology. For additional information about Nabi Biopharmaceuticals, please
visit www.nabi.com.

Forward-Looking Statements

Statements set forth above that are not strictly historical are
forward-looking statements. You can identify these forward-looking statements
because they involve our expectations, intentions, beliefs, plans,
projections, anticipations, or other characterizations of future events or
circumstances. These forward-looking statements are not guarantees of future
performance and are subject to risks and uncertainties that may cause actual
results to differ materially from those in the forward-looking statements as a
result of any number of factors. These factors include, but are not limited
to, risks that are more fully discussed in Nabi's Annual Report on Form 10-K,
as amended, for fiscal year ended December31, 2011, Quarterly Reports on Form
10-Q for the quarters ended March31 and June30, 2012 and definitive proxy
statement for Nabi stockholders special meeting filed with the SEC on
August7, 2012, as supplemented by the supplement dated September25, 2012,
under the captions "Risk Factors" and "Cautionary Statement Regarding
Forward-Looking Statements" and elsewhere in such documents. We do not
undertake to update any of these forward-looking statements or to announce the
results of any revisions to these forward-looking statements except as
required by law.

CONTACT: Nabi Investor Relations
         301-770-3099
         www.nabi.com