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</LabelSeparator><Level>2</Level><ElementName>us-gaap_LiquidityDisclosureTextBlock</ElementName><ElementPrefix>us-gaap_</ElementPrefix><IsBaseElement>true</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsCalendarTitle>false</IsCalendarTitle><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><PreferredLabelRole>terseLabel</PreferredLabelRole><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="eol_PE71016---1310-Q0006_STD_181_20130630_0" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText>&lt;div&gt;
&lt;table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="100%"&gt;
&lt;tr&gt;
&lt;td valign="top" width="4%" align="left"&gt;&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;&lt;b&gt;2.&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="top" align="left"&gt;&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;&lt;b&gt;Liquidity and
management&amp;#x2019;s plans:&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;p style="PADDING-BOTTOM: 0px; MARGIN-TOP: 6px; MARGIN-BOTTOM: 0px"&gt;
&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;Since
inception, the Company has financed its operations principally from
the sale of equity securities, proceeds from short-term borrowings
or convertible notes, funded research arrangements and revenue
generated as a result of its agreements with Meda regarding
ONSOLIS&lt;font style="FONT-FAMILY: Times New Roman" size="1"&gt;&lt;sup style="POSITION: relative; BOTTOM: 0.8ex; VERTICAL-ALIGN: baseline"&gt;&amp;#xAE;&lt;/sup&gt;&lt;/font&gt;
and Endo regarding BEMA&lt;font style="FONT-FAMILY: Times New Roman" size="1"&gt;&lt;sup style="POSITION: relative; BOTTOM: 0.8ex; VERTICAL-ALIGN: baseline"&gt;&amp;#xAE;&lt;/sup&gt;&lt;/font&gt;
Buprenorphine. The Company intends to finance its research and
development and commercialization efforts and its working capital
needs from existing cash, royalty revenue, new sources of
financing, existing and new licensing and commercial partnership
agreements and, potentially, through the exercise of outstanding
Common Stock options and warrants to purchase Common
Stock.&lt;/font&gt;&lt;/p&gt;
&lt;p style="MARGIN-TOP: 12px; MARGIN-BOTTOM: 0px"&gt;&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;Significant new operating
sources during the six months ended June&amp;#xA0;30, 2013 consisted
of:&lt;/font&gt;&lt;/p&gt;
&lt;p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 6px"&gt;
&amp;#xA0;&lt;/p&gt;
&lt;table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="100%"&gt;
&lt;tr&gt;
&lt;td width="4%"&gt;&lt;font size="1"&gt;&amp;#xA0;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="top" width="3%" align="left"&gt;&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;&amp;#x2022;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="top" width="1%"&gt;&lt;font size="1"&gt;&amp;#xA0;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="top" align="left"&gt;
&lt;p align="left"&gt;&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;approximately $0.9 million in net royalties under the Meda
agreements.&lt;/font&gt;&lt;/p&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;p style="MARGIN-TOP: 12px; MARGIN-BOTTOM: 0px"&gt;&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;Significant new operating
sources during the year ended December&amp;#xA0;31, 2012 consisted
of:&lt;/font&gt;&lt;/p&gt;
&lt;p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 6px"&gt;
&amp;#xA0;&lt;/p&gt;
&lt;table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="100%"&gt;
&lt;tr&gt;
&lt;td width="5%"&gt;&lt;font size="1"&gt;&amp;#xA0;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="top" width="2%" align="left"&gt;&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;&amp;#x2022;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="top" width="1%"&gt;&lt;font size="1"&gt;&amp;#xA0;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="top" align="left"&gt;
&lt;p align="left"&gt;&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;approximately $45 million in upfront and milestone payments
from the Endo license agreement (see note 4);&lt;/font&gt;&lt;/p&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 6px"&gt;
&amp;#xA0;&lt;/p&gt;
&lt;table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="100%"&gt;
&lt;tr&gt;
&lt;td width="5%"&gt;&lt;font size="1"&gt;&amp;#xA0;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="top" width="2%" align="left"&gt;&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;&amp;#x2022;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="top" width="1%"&gt;&lt;font size="1"&gt;&amp;#xA0;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="top" align="left"&gt;
&lt;p align="left"&gt;&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;approximately $38.4 million in net proceeds from a registered
direct offering of Common Stock and newly designated Series A
Non-Voting Convertible Preferred Stock, par value $.001 per share
(the &amp;#x201C;Series A Preferred&amp;#x201D;) in November 2012;&lt;/font&gt;&lt;/p&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 6px"&gt;
&amp;#xA0;&lt;/p&gt;
&lt;table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="100%"&gt;
&lt;tr&gt;
&lt;td width="5%"&gt;&lt;font size="1"&gt;&amp;#xA0;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="top" width="2%" align="left"&gt;&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;&amp;#x2022;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="top" width="1%"&gt;&lt;font size="1"&gt;&amp;#xA0;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="top" align="left"&gt;
&lt;p align="left"&gt;&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;approximately $2.1 million from the exercise of stock options;
and&lt;/font&gt;&lt;/p&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 6px"&gt;
&amp;#xA0;&lt;/p&gt;
&lt;table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="100%"&gt;
&lt;tr&gt;
&lt;td width="5%"&gt;&lt;font size="1"&gt;&amp;#xA0;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="top" width="2%" align="left"&gt;&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;&amp;#x2022;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="top" width="1%"&gt;&lt;font size="1"&gt;&amp;#xA0;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="top" align="left"&gt;
&lt;p align="left"&gt;&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;approximately $0.9 million from the exercise of Common Stock
warrants.&lt;/font&gt;&lt;/p&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;p style="MARGIN-TOP: 12px; MARGIN-BOTTOM: 0px; FONT-SIZE: 1px"&gt;
&amp;#xA0;&lt;/p&gt;
&lt;p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px"&gt;&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;On July&amp;#xA0;5, 2013, the
Company, together with Arius One and Arius Two, entered into a $20
million secured loan facility pursuant to a Credit and Security
Agreement (the &amp;#x201C;Credit Agreement&amp;#x201D;) with MidCap
Financial SBIC, LP, as agent and lender (&amp;#x201C;MidCap&amp;#x201D;). The
Company received net proceeds in the aggregate amount of $19.9
million and will use the loan proceeds for general corporate
purposes or other activities permitted under the Credit Agreement.
See Note 12.&lt;/font&gt;&lt;/p&gt;
&lt;p style="MARGIN-TOP: 12px; MARGIN-BOTTOM: 0px"&gt;&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;At June&amp;#xA0;30, 2013, the
Company had cash and cash equivalents of approximately $37.4
million. The Company used $25.8 million of cash from operations
during the six months ended June&amp;#xA0;30, 2013. As of June&amp;#xA0;30,
2013, the Company had stockholders&amp;#x2019; equity of $27.1 million,
versus $49.8 million at December&amp;#xA0;31, 2012. The Company&amp;#x2019;s
existing cash (after giving effect to the proceeds of the loan from
MidCap), supplemented with other expected cash inflows from
milestones, royalties and the aforementioned loan, is anticipated
by management to be sufficient to fully fund the Company&amp;#x2019;s
operations through the fourth quarter of 2014 at the planned level
of expenditures. Certain planned expenditures are discretionary and
could be deferred if the Company is required to do so to fund
critical operations.&lt;/font&gt;&lt;/p&gt;
&lt;p style="PADDING-BOTTOM: 0px; MARGIN-TOP: 12px; MARGIN-BOTTOM: 0px"&gt;
&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;Accordingly,
additional capital will be required to support commercialization
activities for BUNAVAIL&amp;#x2122;, clinical development programs for
BEMA&lt;font style="FONT-FAMILY: Times New Roman" size="1"&gt;&lt;sup style="POSITION: relative; BOTTOM: 0.8ex; VERTICAL-ALIGN: baseline"&gt;&amp;#xAE;&lt;/sup&gt;&lt;/font&gt;
Buprenorphine (the scale of which is being governed in large part
by the requirements of the Company&amp;#x2019;s agreement with Endo),
the reformulation project for and anticipated commercial relaunch
of ONSOLIS&lt;font style="FONT-FAMILY: Times New Roman" size="1"&gt;&lt;sup style="POSITION: relative; BOTTOM: 0.8ex; VERTICAL-ALIGN: baseline"&gt;&amp;#xAE;&lt;/sup&gt;&lt;/font&gt;,
planned development of the Company&amp;#x2019;s Clonidine Topical Gel
product for painful diabetic neuropathy and general working
capital. Based on product development timelines and agreements with
the Company&amp;#x2019;s development partners, the ability to scale up
or reduce personnel and associated costs are factors considered
throughout the product development life cycle. Available resources
may be consumed more rapidly than currently anticipated, resulting
in the need for additional funding.&lt;/font&gt;&lt;/p&gt;
&lt;/div&gt;</NonNumbericText><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>nonnum:textBlockItemType</ElementDataType><SimpleDataType>na</SimpleDataType><ElementDefenition>Disclosure of accounting policy for reporting when there is a substantial doubt about an entity's ability to continue as a going concern for a reasonable period of time (generally a year from the balance sheet date). Disclose: (a) pertinent conditions and events giving rise to the assessment of substantial doubt about the entity's ability to continue as a going concern for a reasonable period of time, (b) the possible effects of such conditions and events, (c) management's evaluation of the significance of those conditions and events and any mitigating factors, (d) possible discontinuance of operations, (e) management's plans (including relevant prospective financial information), and (f) information about the recoverability or classification of recorded asset amounts or the amounts or classification of liabilities. If management's plans alleviate the substantial doubt about the entity's ability to continue as a going concern, disclosure of the principal conditions and events that initially raised the substantial doubt about the entity's ability to continue as a going concern would be expected to be considered. Disclose whether operations for the current or prior years generated sufficient cash to cover current obligations, whether waivers were obtained from creditors relating to the company's default under the provisions of debt agreements and possible effects of such conditions and events, such as: whether there is a possible need to obtain additional financing (debt or equity) or to liquidate certain holdings to offset future cash flow deficiencies. Disclose appropriate parent company information when parent is dependent upon remittances from subsidiaries to satisfy its obligations.</ElementDefenition><ElementReferences>No definition available.</ElementReferences><IsTotalLabel>false</IsTotalLabel><UnitID>0</UnitID><Label>Liquidity and management's plans</Label></Row></Rows><Footnotes /><IsEquityReport>false</IsEquityReport><ReportName>Liquidity and management's plans</ReportName><MonetaryRoundingLevel>UnKnown</MonetaryRoundingLevel><SharesRoundingLevel>UnKnown</SharesRoundingLevel><PerShareRoundingLevel>UnKnown</PerShareRoundingLevel><ExchangeRateRoundingLevel>UnKnown</ExchangeRateRoundingLevel><HasCustomUnits>true</HasCustomUnits><IsEmbedReport>false</IsEmbedReport><IsMultiCurrency>false</IsMultiCurrency><ReportType>Sheet</ReportType><RoleURI>http://www.bdsi.com/taxonomy/role/NotesToFinancialStatementsLiquidityDisclosureTextBlock</RoleURI><NumberOfCols>1</NumberOfCols><NumberOfRows>2</NumberOfRows></InstanceReport>
