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</LabelSeparator><Level>2</Level><ElementName>bpth_AccountsPayableDisclosureTextBlock</ElementName><ElementPrefix>bpth_</ElementPrefix><IsBaseElement>false</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>verboseLabel</PreferredLabelRole><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="P01_01_2013To06_30_2013" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText>              &lt;table border="0" style="clear:both;width:100%; table-layout:fixed;"&gt;  &lt;tr&gt;  &lt;td&gt;&lt;/td&gt;  &lt;/tr&gt;  &lt;/table&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif "&gt;  &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;MARGIN: 0in 0in 0pt; FONT-SIZE: 10pt"&gt;  &lt;table style="clear:both;MARGIN-TOP: 0px; FONT: 10pt Times New Roman, Times, Serif; MARGIN-BOTTOM: 0px"   cellspacing="0" cellpadding="0"&gt;  &lt;tr style="TEXT-ALIGN: justify; VERTICAL-ALIGN: top"&gt;  &lt;td style="TEXT-ALIGN: left; WIDTH: 0.25in"&gt;  &lt;div&gt;&lt;b&gt;4.&lt;/b&gt;&lt;/div&gt;  &lt;/td&gt;  &lt;td style="TEXT-ALIGN: justify"&gt;  &lt;div&gt;&lt;b&gt;Accounts Payable&lt;/b&gt;&lt;/div&gt;  &lt;/td&gt;  &lt;/tr&gt;  &lt;/table&gt;  &lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  &amp;#160;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  As of June 30, 2013, Current Liabilities included accounts payable  of $&lt;font style=" FONT-SIZE: 10pt"&gt;165,897&lt;/font&gt; comprised  primarily of approximate amounts owed to the Company&amp;#8217;s drug  contract manufacturers totaling $&lt;font style=" FONT-SIZE: 10pt"&gt;114,200&lt;/font&gt;, $&lt;font style=" FONT-SIZE: 10pt"&gt;13,900&lt;/font&gt; to several companies involved in  research and development testing, &lt;font style="COLOR: black"&gt;$&lt;font  style=" FONT-SIZE: 10pt"&gt;6,800&lt;/font&gt; in fees for an industry  conference at which the Company will be making a corporate  presentation,&lt;/font&gt; $&lt;font style=" FONT-SIZE: 10pt"&gt;6,000&lt;/font&gt;  to outside consultants and $&lt;font style=" FONT-SIZE: 10pt"&gt;15,900&lt;/font&gt; to the Company&amp;#8217;s attorneys  and auditors. As of June 30, 2013 Current Liabilities included  accounts payable related party totaling $&lt;font style=" FONT-SIZE: 10pt"&gt;10,017&lt;/font&gt; comprised of Technology License  patent maintenance fees. (See Note 2.). As of December 31, 2012,  Current Liabilities included accounts payable $&lt;font style=" FONT-SIZE: 10pt"&gt;57,000&lt;/font&gt; and accounts payable related party  of $&lt;font style=" FONT-SIZE: 10pt"&gt;8,582&lt;/font&gt;, which amounts were  subsequently paid in 2013.&lt;/div&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>Accounts Payable Disclosure [Text Block]</ElementDefenition><ElementReferences>No definition available.</ElementReferences><IsTotalLabel>false</IsTotalLabel><UnitID>0</UnitID><Label>Accounts Payable</Label></Row></Rows><Footnotes /><IsEquityReport>false</IsEquityReport><ReportName>Accounts Payable</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.biopathholdings.com/role/AccountsPayable</RoleURI><NumberOfCols>1</NumberOfCols><NumberOfRows>2</NumberOfRows></InstanceReport>
