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    <nameOfIssuer>ARGENX SE</nameOfIssuer>
    <titleOfClass>Sponsored ADR</titleOfClass>
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    <nameOfIssuer>ARROWHEAD PHARMACEUTICALS INC</nameOfIssuer>
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    <nameOfIssuer>ASCENDIS PHARMA</nameOfIssuer>
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    <cusip>K08588103</cusip>
    <value>1363235526</value>
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    <titleOfClass>Common</titleOfClass>
    <cusip>05338F306</cusip>
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    <cusip>15102K100</cusip>
    <value>355708000</value>
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      <Sole>3400000</Sole>
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    <nameOfIssuer>CYTOKINETICS INC</nameOfIssuer>
    <titleOfClass>Common</titleOfClass>
    <cusip>23282W605</cusip>
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    <nameOfIssuer>DAMORA THERAPEUTICS INC</nameOfIssuer>
    <titleOfClass>Common</titleOfClass>
    <cusip>36322Q206</cusip>
    <value>98395830</value>
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      <sshPrnamt>3783000</sshPrnamt>
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      <None>0</None>
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    <nameOfIssuer>DEFINIUM THERAPEUTICS INC</nameOfIssuer>
    <titleOfClass>Common</titleOfClass>
    <cusip>24477V105</cusip>
    <value>338165292</value>
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    <nameOfIssuer>FAETH THERAPEUTICS INC</nameOfIssuer>
    <titleOfClass>COMMON</titleOfClass>
    <cusip>81728A207</cusip>
    <value>36100975</value>
    <shrsOrPrnAmt>
      <sshPrnamt>1444039</sshPrnamt>
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      <None>0</None>
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    <nameOfIssuer>GH RESEARCH PLC</nameOfIssuer>
    <titleOfClass>ORDINARY SHARES</titleOfClass>
    <cusip>G3855L106</cusip>
    <value>48384000</value>
    <shrsOrPrnAmt>
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      <Sole>1800000</Sole>
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      <None>0</None>
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    <nameOfIssuer>HEMAB THERAPEUTICS HLDGS INC</nameOfIssuer>
    <titleOfClass>Common</titleOfClass>
    <cusip>423494103</cusip>
    <value>70710760</value>
    <shrsOrPrnAmt>
      <sshPrnamt>1925150</sshPrnamt>
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    <nameOfIssuer>KRYSTAL BIOTECH INC</nameOfIssuer>
    <titleOfClass>Common</titleOfClass>
    <cusip>501147102</cusip>
    <value>1073713003</value>
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    <nameOfIssuer>KYMERA THERAPEUTICS INC</nameOfIssuer>
    <titleOfClass>Common</titleOfClass>
    <cusip>501575104</cusip>
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    <nameOfIssuer>LEXEO THERAPEUTICS INC</nameOfIssuer>
    <titleOfClass>Common</titleOfClass>
    <cusip>52886X107</cusip>
    <value>6932175</value>
    <shrsOrPrnAmt>
      <sshPrnamt>1489189</sshPrnamt>
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    <nameOfIssuer>MADRIGAL PHARMACEUTICALS INC</nameOfIssuer>
    <titleOfClass>Common</titleOfClass>
    <cusip>558868105</cusip>
    <value>984408154</value>
    <shrsOrPrnAmt>
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      <None>0</None>
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    <nameOfIssuer>OCULAR THERAPEUTIX INC</nameOfIssuer>
    <titleOfClass>Common</titleOfClass>
    <cusip>67576A100</cusip>
    <value>123142800</value>
    <shrsOrPrnAmt>
      <sshPrnamt>12540000</sshPrnamt>
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      <Sole>12540000</Sole>
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      <None>0</None>
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    <nameOfIssuer>REVOLUTION MEDICINES INC</nameOfIssuer>
    <titleOfClass>Common</titleOfClass>
    <cusip>76155X100</cusip>
    <value>430182160</value>
    <shrsOrPrnAmt>
      <sshPrnamt>2297000</sshPrnamt>
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      <Sole>2297000</Sole>
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    <nameOfIssuer>SEPTERNA INC</nameOfIssuer>
    <titleOfClass>Common</titleOfClass>
    <cusip>81734D104</cusip>
    <value>44792875</value>
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      <sshPrnamt>1337500</sshPrnamt>
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      <Sole>1337500</Sole>
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    <nameOfIssuer>STRUCTURE THERAPEUTICS INC</nameOfIssuer>
    <titleOfClass>SPONSORED ADS</titleOfClass>
    <cusip>86366E106</cusip>
    <value>351836637</value>
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    <nameOfIssuer>TAYSHA GENE THERAPIES INC</nameOfIssuer>
    <titleOfClass>Common</titleOfClass>
    <cusip>877619106</cusip>
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      <sshPrnamt>23888888</sshPrnamt>
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      <Sole>23888888</Sole>
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    <nameOfIssuer>UNIQURE NV</nameOfIssuer>
    <titleOfClass>Common</titleOfClass>
    <cusip>N90064101</cusip>
    <value>309881409</value>
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    <nameOfIssuer>UNITED THERAPEUTICS CORP</nameOfIssuer>
    <titleOfClass>Common</titleOfClass>
    <cusip>91307C102</cusip>
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    <nameOfIssuer>VERA THERAPEUTICS INC</nameOfIssuer>
    <titleOfClass>Common</titleOfClass>
    <cusip>92337R101</cusip>
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    <nameOfIssuer>VIRIDIAN THERAPEUTICS INC</nameOfIssuer>
    <titleOfClass>Common</titleOfClass>
    <cusip>92790C104</cusip>
    <value>45925000</value>
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    <nameOfIssuer>WHITEHAWK THERAPEUTICS INC</nameOfIssuer>
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    <cusip>00032Q104</cusip>
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