SC TO-I/A

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SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549

SCHEDULE TO-I/A
(RULE 14d-100)

TENDER OFFER STATEMENT UNDER SECTION 14(d)(1) OR 13(e)(1)
OF THE SECURITIES EXCHANGE ACT OF 1934
(AMENDMENT NO. 4)

PRESSURE BIOSCIENCES, INC.
(Name of Subject Company (Issuer))

PRESSURE BIOSCIENCES, INC.
(Names of Filing Persons (offeror and issuer)

COMMON STOCK, $.01 PAR VALUE PER SHARE
and associated
Preferred Share Purchase Rights
(Title of Class of Securities)

74112E 10 9
(CUSIP Number of Class of Securities)

Richard T. Schumacher
President and Chief Executive Officer
Pressure BioSciences, Inc.
217 Perry Parkway, Gaithersburg, MD 20877
(301) 208-8100
(Name, Address and Telephone Number of Person Authorized to Receive
Notices and Communications on Behalf of the Filing Person)

Copy to:

Steven R. London, Esq.
Brown Rudnick Berlack Israels LLP
One Financial Center
Boston, MA 02111
(617) 856-8200

CALCULATION OF FILING FEE

Transaction Valuation*	Amount of Filing Fee**
$19,250,000	$2,266

*

Calculated solely for purposes of determining the filing fee. The transaction value assumes the purchase by the registrant of 5,500,000 shares of its common stock at $3.50 per share.

**

$117.70 per $1,000,000 of the transaction valuation.

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Check the box if any part of the fee is offset as provided by Rule 0-11(a)(2) and identify the filing with which the offsetting fee was previously paid. Identify the previous filing by registration statement number, or the Form or Schedule and the date of its filing.

Amount Previously Paid:	$2,266
Form or Registration No.:	Schedule TO-I
Filing Party:	Pressure BioSciences, Inc.
Date Filed:	December 27, 2004

o

Check the box if the filing relates solely to preliminary communications made before the commencement of a tender offer.

Check the appropriate boxes below to designate any transactions to which the statement relates:

o

third-party tender offer subject to Rule 14d-1.

ý

issuer tender offer subject to Rule 13e-4.

ý

going-private transaction subject to Rule 13e-3.

o

amendment to Schedule 13D under Rule 13d-2.

Check the following box if the filing is a final amendment reporting the results of the tender offer: o

INTRODUCTION

This Amendment No. 4 amends and supplements the Tender Offer Statement on Schedule TO-I dated December 27, 2004, as amended and supplemented by Amendment No. 1 to Schedule TO-I filed on January 21, 2005, Amendment No. 2 to Schedule TO-I filed on January 25, 2005 and Amendment No. 3 to Schedule TO-I filed on February 3, 2005 (the "Schedule TO-I") relating to the issuer tender offer by Pressure Biosciences, Inc., a Massachusetts corporation formerly known as Boston Biomedica, Inc. (the "Company" or "Pressure BioSciences"), to purchase up to 5,500,000 shares of its common stock, $0.01 par value per share (the "Shares"), at a purchase price of $3.50 per Share, net to the seller in cash, without interest. Pressure BioSciences' tender offer, which expired on February 11, 2005, was made upon the terms and subject to the conditions set forth in the Offer to Purchase dated December 27, 2004 (the "Offer to Purchase"), a copy of which is attached as Exhibit (a)(1)(A) to the Company's Schedule TO-I, and in the related Letter of Transmittal (the "Letter of Transmittal"), a copy of which is attached as Exhibit (a)(1)(B) to the Company's Schedule TO-I (and which, together with the Offer to Purchase, as amended or supplemented from time to time, constitute the "Offer") and are herein incorporated by reference.

        This Amendment No. 4 is filed in satisfaction of the reporting requirements of Rule 13e-4(c) promulgated under the Securities Exchange Act of 1934, as amended, which requires a final amendment to Schedule TO to be filed to report the results of the Offer.

        The following items of Schedule TO-I are amended and supplemented as set forth below:

Item 4. TERMS OF THE TRANSACTION

(a)    Material Terms

        (1)    Tender Offers

        Item 4(a)(1)(iii) of Schedule TO-I is hereby further amended and supplemented to include the following:

•

The Offer expired at 10:00 a.m., Eastern Standard Time, on Friday, February 11, 2005. The Company accepted for payment a total of 5,210,001 shares of common stock, which includes 761,275 shares which were issued upon exercise of stock options, at a purchase price of $3.50 per share.

Item 12. EXHIBITS

(a)	(1)(A)	Offer to Purchase dated December 27, 2004 (1)
(a)	(1)(B)	Letter of Transmittal(1)
(a)	(1)(C)	Notice of Guaranteed Delivery of Shares of Common Stock(1)
(a)	(1)(D)	Letter to Brokers, Dealers, Commercial Banks, Trust Companies and Other Nominees(1)
(a)	(1)(E)	Letter to Clients for use by Brokers, Dealers, Commercial Banks, Trust Companies and Other Nominees(1)
(a)	(1)(F)	Guidelines for Certification of Taxpayer Identification Number on Substitute Form W-9(1)
(a)	(5)(A)	Press Release dated January 25, 2005(2)
(a)	(5)(B)	Press Release dated February 3, 2005(3)
(a)	(5)(C)	Press Release dated February 14, 2005

(1)

The foregoing exhibits were filed as exhibits to the Company's Schedule TO-I filed with the Commission on December 27, 2004, and are incorporated herein by this reference.

(2)

The foregoing exhibit was filed as an exhibit to the Company's Amendment No. 2 to Schedule TO-I filed with the Commission on January 25, 2005, and is incorporated herein by this reference.

(3)

The foregoing exhibit was filed as an exhibit to the Company's Amendment No. 3 to Schedule TO-I filed with the Commission on February 3, 2005, and is incorporated herein by this reference.

SIGNATURES

        After due inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

PRESSURE BIOSCIENCES, INC.
By:	/s/  RICHARD T. SCHUMACHER Name: Richard T. Schumacher Title: President and Chief Executive Officer
Dated: February 14, 2005

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INTRODUCTION

Item 4. TERMS OF THE TRANSACTION
Item 12. EXHIBITS

SIGNATURES

EX-99.(A)(5)(C)

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Exhibit (a)(5)(C)

FOR IMMEDIATE RELEASE

Investor Contacts:

Richard T. Schumacher, Founder & CEO	Pressure BioSciences, Inc.
R. Wayne Fritzsche, Chairman	(301) 208-8100 (T)

PRESSURE BIOSCIENCES REPORTS RESULTS OF TENDER OFFER

PBI Notifies Nasdaq of Plans to Transfer to Nasdaq SmallCap Market

        GAITHERSBURG, MD, February 14, 2005—Pressure BioSciences, Inc. (NASDAQ: PBIO) today announced the final results of its issuer tender offer to purchase up to 5,500,000 shares of its common stock at a purchase price of $3.50 per share. The tender offer expired at 10:00 a.m., Eastern Standard Time, on February 11, 2005. Based on the final count by the depositary for the tender offer, 5,210,001 shares of common stock, which includes 761,275 shares issued upon exercise of stock options, were properly tendered and not withdrawn. The Company is accepting for purchase all 5,210,001 shares at a purchase price of $3.50 per share in accordance with the terms of the offer. The aggregate purchase price to be paid for the tendered shares, after deducting the aggregate exercise price for the 761,275 shares issued upon exercise of stock options, is $16.1 million. As a result of the completion of the tender offer, immediately following payment for the tendered shares, the Company will have 2,424,189 shares of common stock outstanding. Any questions regarding the tender offer may be directed to Computershare Trust Company at (800) 962-4284, ext. 4732.

        As a result of the number of shares that have been tendered and accepted for purchase in the tender offer, the Company has reviewed the continued listing requirements of the Nasdaq National Market and does not believe it will meet the $10 million stockholders' equity requirement pursuant to Rule 4450(a)(3) of the Nasdaq Marketplace Rules. Accordingly, on February 14, 2005, the Company notified the Nasdaq Stock Market that it believes it may not be in compliance with the stockholders' equity continued listing requirement of the Nasdaq National Market and that it plans to make application to transfer to the Nasdaq SmallCap Market. The Company believes it meets the listing requirements to transfer from the Nasdaq National Market to the Nasdaq SmallCap Market and plans to make the necessary application and filings with the Nasdaq Stock Market as soon as possible.

About Pressure BioSciences, Inc.

        Following the sale of substantially all the assets and selected liabilities of its BBI Diagnostics and BBI Biotech Divisions to SeraCare Life Sciences, Inc. on September 14, 2004, Boston Biomedica, Inc. changed its name to Pressure BioSciences, Inc (PBI). PBI is a publicly traded, early-stage company focused on the development of a novel technology called Pressure Cycling Technology (PCT). PCT uses cycles of hydrostatic pressure between ambient and ultra-high levels (35,000 psi and greater) to control bio-molecular interactions. PBI currently holds 13 US and foreign patents covering multiple applications of PCT in the life sciences field, including in such areas as genomic and proteomic sample preparation, pathogen inactivation, control of enzymes, immunodiagnostics, and protein purification. PBI owns a 30% passive investment in Source Scientific, LLC, an instrumentation company that develops and manufactures PBI's PCT equipment, as well as a 4.45% passive investment in Panacos Pharmaceuticals, an antiviral drug discovery and development company.

Forward Looking Statements

        Statements contained in this press release regarding the Company's intentions, hopes, beliefs, expectations or predictions of the future are "forward-looking" statements within the meaning of the

Private Securities Litigation Reform Act of 1995. These statements include the Company's belief that it will be able to satisfy the listing requirements under the Nasdaq SmallCap Market and that it will be able to transfer from the Nasdaq National Market to the Nasdaq SmallCap Market. These statements are based upon the Company's current expectations, forecasts, and assumptions that are subject to risks, uncertainties and other factors that could cause actual outcomes and results to differ materially from those indicated by these forward-looking statements. These risks, uncertainties and other factors include: the potential rejection of the Company's application to transfer from the Nasdaq National Market to the Nasdaq SmallCap Market; the possible future delisting of the Company's common stock by Nasdaq if the Company's fails to meet the listing requirements of the Nasdaq SmallCap Market; the risk that the Company's common stock will become a "penny stock" as defined under the SEC rules, which may adversely affect a stockholder's ability to sell shares in the secondary market at the times and in the quantities desired; and other risks and uncertainties identified in the Company's filings with the Securities and Exchange Commission. The Company undertakes no obligation to update any of the information included in this release, except as otherwise required by law.

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Exhibit (a)(5)(C)

PRESSURE BIOSCIENCES REPORTS RESULTS OF TENDER OFFER
PBI Notifies Nasdaq of Plans to Transfer to Nasdaq SmallCap Market