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				</style></head><body lang="en-US" text="#000000" bgcolor="#ffffff"><hr class="header"><br><hr class="headerThin"><div class="contentwrapper"><table role="presentation" id="scheader"><tr><td class="tableClassNoBorderAlignCenter" style="font-size:2em;">
						SECURITIES AND EXCHANGE COMMISSION
						<br>
						Washington, D.C. 20549
					</td></tr><tr><td class="tableClassNoBorderAlignCenter"><br><br><div style="font-size:1.5em;">
									SCHEDULE 13D
								</div><br><div style="font-size:1.2em;">
							Under the Securities Exchange Act of 1934
						</div><br><div class="information" style="text-align:center; font-weight:bold;">
									(Amendment No. <span style="color:blue;">3</span>)
								</div><br><br></td></tr><tr><td class="center"><div class="information" style="text-align:center; font-weight:bold; color:blue;">Atara Biotherapeutics, Inc.</div><div class="information" style="text-align:center; font-weight:bold;"><hr class="separatorThin">(Name of Issuer)</div><br><br></td></tr><tr><td class="center"><div class="information" style="text-align:center; font-weight:bold; color:blue;">Common Stock, par value $0.0001 per share</div><div class="information" style="text-align:center; font-weight:bold;"><hr class="separatorThin">(Title of Class of Securities)</div><br><br></td></tr><table border="1"><tr><td><div class="information" style="text-align:center; font-weight:bold; color:blue;">046513206</div><div class="information" style="text-align:center; font-weight:bold;"><hr class="separatorThin">(CUSIP Number)</div></td></tr><br><br></table><tr><td class="center"><div class="information" style="text-align:center; font-weight:bold; color:blue;">Redmile Group, LLC<br>900 Larkspur Landing Circle, Suite 270,
								<br>Larkspur,
								CA,
								94939<br>(415) 489-9980</div><div class="information" style="text-align:center; font-weight:bold;"><hr class="separatorThin">(Name, Address and Telephone Number of Person Authorized to
									Receive Notices and Communications)</div></td></tr><tr><td class="center"><div class="information" style="text-align:center; font-weight:bold; color:blue;">07/22/2026</div><div class="information" style="text-align:center; font-weight:bold;"><hr class="separatorThin">(Date of Event Which Requires Filing of This Statement)</div></td></tr></table><br><br><div class="information" style="text-align:justify">
				If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§ 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box.
				<img src="/Images/box-checked.jpg" alt="Checkbox checked"></div><br><div class="information" style="text-align:justify">
				The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the
				Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other
				provisions of the Act (however, see the Notes).
			</div></div><hr class="headerThin"><hr class="header"><br><br>
  <div style="display:none">
			schemaVersion:
			</div>
<div class="content"><div class="form1"></div></div>
  <div class="content"><div class="form1"><table><tr><td class="center"><br><br><p><div align="center" style="font-size:1.2em;">
									SCHEDULE 13D
								</div></p></td></tr></table><table role="presentation" class="tableClass" id="cusipNumber"><tr class="tableClass"><td width="7%" style="font-weight:bold;">CUSIP Number(s):</td><td width="75%"><div style="font-size:.9em; color:#000000">046513206</div></td></tr></table><br><br><table role="presentation" class="tableClass" id="reportingPersonDetails"><tr class="tableClass"><td width="8%" class="tableClassValign">1</td><td width="92%" class="tableClass">
					Name of reporting person
					<br><br><div class="text">Redmile Group, LLC</div></td></tr><tr><td width="8%" class="tableClassValign">2</td><td width="92%" class="tableClass">Check the appropriate box if a member of a Group (See Instructions)
				<br><br><div class="text"><img src="/Images/box-unchecked.jpg" alt="Checkbox not checked">  (a)
					<br><img src="/Images/box-unchecked.jpg" alt="Checkbox not checked">  (b)	
				</div></td></tr><tr class="tableClassWithBgBlack"><td width="8%" class="tableClassValign">3</td><td width="92%" class="tableClass">SEC use only</td></tr><tr><td width="8%" class="tableClassValign">4</td><td width="92%" class="tableClass">
					Source of funds (See Instructions)
					<br><br><div class="text">OO</div></td></tr><tr><td width="8%" class="tableClassValign">5</td><td width="92%" class="tableClass">
					Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)
					<br><br><img src="/Images/box-unchecked.jpg" alt="Checkbox not checked"></td></tr><tr><td width="8%" class="tableClassValign">6</td><td width="92%" class="tableClass">Citizenship or place of organization
				<br><br><div class="text">
				DELAWARE
			</div></td></tr><tr><td width="8%" class="tableClassValign">Number of Shares Beneficially Owned by Each Reporting Person With:</td><td width="92%" class="tableClass"><table class="innerTableClass"><tr><td width="8%" class="innerTableClassRightValign">7</td><td width="92%" class="tableClassInnerLeft">Sole Voting Power
							<br><br><div class="text">0.00</div></td></tr><tr><td width="8%" class="innerTableClassRightValign">8</td><td width="92%" class="tableClassInnerLeft">Shared Voting Power
							<br><br><div class="text">950,994.00</div></td></tr><tr><td width="8%" class="innerTableClassRightValign">9</td><td width="92%" class="tableClassInnerLeft">Sole Dispositive Power
							<br><br><div class="text">0.00</div></td></tr><tr><td width="8%" class="innerTableClassRightValignBottomLess">10</td><td width="92%" class="tableClassInnerLeftBottomLess">Shared Dispositive Power
							<br><br><div class="text">950,994.00</div></td></tr></table></td></tr><tr><td width="8%" class="tableClassValign">11</td><td width="92%" class="tableClass">Aggregate amount beneficially owned by each reporting person
				<br><br><div class="text">950,994.00</div></td></tr><tr><td width="8%" class="tableClassValign">12</td><td width="92%" class="tableClass">Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)
				<br><br><img src="/Images/box-unchecked.jpg" alt="Checkbox not checked"></td></tr><tr><td width="8%" class="tableClassValign">13</td><td width="92%" class="tableClass">Percent of class represented by amount in Row (11)
				<br><br><div class="text">9.9 % </div></td></tr><tr><td width="8%" class="tableClassValign">14</td><td width="92%" class="tableClass">Type of Reporting Person (See Instructions)
				<br><br><div class="text">IA, OO</div></td></tr></table><br><div style="display: flex;"><div style="font-size: 0.9em; font-weight: bold; margin-right: 5px;">
					Comment for Type of Reporting Person:
				</div><div class="largetext" style="text-align:justify">(1) The source of funds was working capital of certain private investment funds managed by Redmile Group, LLC (the "Redmile Funds"), including Redmile Biopharma Investments II, L.P. ("RBI II") and Redmile Strategic Long Only Trading Sub, Ltd. ("Redmile Long Only").

(2) The information in Item 5(a) relating to the shares of common stock, par value $0.0001 per share, of the Issuer (the "Common Stock") that are or may be deemed beneficially owned by Redmile Group, LLC ("Redmile") and the calculation of the percent of such class of securities is incorporated by reference herein.</div></div><table><tr><td class="center"><br><br><p><div align="center" style="font-size:1.2em;">
									SCHEDULE 13D
								</div></p></td></tr></table><table role="presentation" class="tableClass" id="cusipNumber"><tr class="tableClass"><td width="7%" style="font-weight:bold;">CUSIP Number(s):</td><td width="75%"><div style="font-size:.9em; color:#000000">046513206</div></td></tr></table><br><br><table role="presentation" class="tableClass" id="reportingPersonDetails"><tr class="tableClass"><td width="8%" class="tableClassValign">1</td><td width="92%" class="tableClass">
					Name of reporting person
					<br><br><div class="text">Green Jeremy</div></td></tr><tr><td width="8%" class="tableClassValign">2</td><td width="92%" class="tableClass">Check the appropriate box if a member of a Group (See Instructions)
				<br><br><div class="text"><img src="/Images/box-unchecked.jpg" alt="Checkbox not checked">  (a)
					<br><img src="/Images/box-unchecked.jpg" alt="Checkbox not checked">  (b)	
				</div></td></tr><tr class="tableClassWithBgBlack"><td width="8%" class="tableClassValign">3</td><td width="92%" class="tableClass">SEC use only</td></tr><tr><td width="8%" class="tableClassValign">4</td><td width="92%" class="tableClass">
					Source of funds (See Instructions)
					<br><br><div class="text">OO</div></td></tr><tr><td width="8%" class="tableClassValign">5</td><td width="92%" class="tableClass">
					Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)
					<br><br><img src="/Images/box-unchecked.jpg" alt="Checkbox not checked"></td></tr><tr><td width="8%" class="tableClassValign">6</td><td width="92%" class="tableClass">Citizenship or place of organization
				<br><br><div class="text">
				UNITED KINGDOM
			</div></td></tr><tr><td width="8%" class="tableClassValign">Number of Shares Beneficially Owned by Each Reporting Person With:</td><td width="92%" class="tableClass"><table class="innerTableClass"><tr><td width="8%" class="innerTableClassRightValign">7</td><td width="92%" class="tableClassInnerLeft">Sole Voting Power
							<br><br><div class="text">0.00</div></td></tr><tr><td width="8%" class="innerTableClassRightValign">8</td><td width="92%" class="tableClassInnerLeft">Shared Voting Power
							<br><br><div class="text">950,994.00</div></td></tr><tr><td width="8%" class="innerTableClassRightValign">9</td><td width="92%" class="tableClassInnerLeft">Sole Dispositive Power
							<br><br><div class="text">0.00</div></td></tr><tr><td width="8%" class="innerTableClassRightValignBottomLess">10</td><td width="92%" class="tableClassInnerLeftBottomLess">Shared Dispositive Power
							<br><br><div class="text">950,994.00</div></td></tr></table></td></tr><tr><td width="8%" class="tableClassValign">11</td><td width="92%" class="tableClass">Aggregate amount beneficially owned by each reporting person
				<br><br><div class="text">950,994.00</div></td></tr><tr><td width="8%" class="tableClassValign">12</td><td width="92%" class="tableClass">Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)
				<br><br><img src="/Images/box-unchecked.jpg" alt="Checkbox not checked"></td></tr><tr><td width="8%" class="tableClassValign">13</td><td width="92%" class="tableClass">Percent of class represented by amount in Row (11)
				<br><br><div class="text">9.9 % </div></td></tr><tr><td width="8%" class="tableClassValign">14</td><td width="92%" class="tableClass">Type of Reporting Person (See Instructions)
				<br><br><div class="text">IN, HC</div></td></tr></table><br><div style="display: flex;"><div style="font-size: 0.9em; font-weight: bold; margin-right: 5px;">
					Comment for Type of Reporting Person:
				</div><div class="largetext" style="text-align:justify">(1) The source of funds was working capital of the Redmile Funds, including RBI II and Redmile Long Only.

(2) The information in Item 5(a) relating to the shares of Common Stock that are or may be deemed beneficially owned by Jeremy Green and the calculation of the percent of such class of securities is incorporated by reference herein.</div></div><table><tr><td class="center"><br><br><p><div align="center" style="font-size:1.2em;">
									SCHEDULE 13D
								</div></p></td></tr></table><table role="presentation" class="tableClass" id="cusipNumber"><tr class="tableClass"><td width="7%" style="font-weight:bold;">CUSIP Number(s):</td><td width="75%"><div style="font-size:.9em; color:#000000">046513206</div></td></tr></table><br><br><table role="presentation" class="tableClass" id="reportingPersonDetails"><tr class="tableClass"><td width="8%" class="tableClassValign">1</td><td width="92%" class="tableClass">
					Name of reporting person
					<br><br><div class="text">Redmile Biopharma Investments II, L.P.</div></td></tr><tr><td width="8%" class="tableClassValign">2</td><td width="92%" class="tableClass">Check the appropriate box if a member of a Group (See Instructions)
				<br><br><div class="text"><img src="/Images/box-unchecked.jpg" alt="Checkbox not checked">  (a)
					<br><img src="/Images/box-unchecked.jpg" alt="Checkbox not checked">  (b)	
				</div></td></tr><tr class="tableClassWithBgBlack"><td width="8%" class="tableClassValign">3</td><td width="92%" class="tableClass">SEC use only</td></tr><tr><td width="8%" class="tableClassValign">4</td><td width="92%" class="tableClass">
					Source of funds (See Instructions)
					<br><br><div class="text">WC</div></td></tr><tr><td width="8%" class="tableClassValign">5</td><td width="92%" class="tableClass">
					Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)
					<br><br><img src="/Images/box-unchecked.jpg" alt="Checkbox not checked"></td></tr><tr><td width="8%" class="tableClassValign">6</td><td width="92%" class="tableClass">Citizenship or place of organization
				<br><br><div class="text">
				DELAWARE
			</div></td></tr><tr><td width="8%" class="tableClassValign">Number of Shares Beneficially Owned by Each Reporting Person With:</td><td width="92%" class="tableClass"><table class="innerTableClass"><tr><td width="8%" class="innerTableClassRightValign">7</td><td width="92%" class="tableClassInnerLeft">Sole Voting Power
							<br><br><div class="text">0.00</div></td></tr><tr><td width="8%" class="innerTableClassRightValign">8</td><td width="92%" class="tableClassInnerLeft">Shared Voting Power
							<br><br><div class="text">631,020.00</div></td></tr><tr><td width="8%" class="innerTableClassRightValign">9</td><td width="92%" class="tableClassInnerLeft">Sole Dispositive Power
							<br><br><div class="text">0.00</div></td></tr><tr><td width="8%" class="innerTableClassRightValignBottomLess">10</td><td width="92%" class="tableClassInnerLeftBottomLess">Shared Dispositive Power
							<br><br><div class="text">631,020.00</div></td></tr></table></td></tr><tr><td width="8%" class="tableClassValign">11</td><td width="92%" class="tableClass">Aggregate amount beneficially owned by each reporting person
				<br><br><div class="text">631,020.00</div></td></tr><tr><td width="8%" class="tableClassValign">12</td><td width="92%" class="tableClass">Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)
				<br><br><img src="/Images/box-unchecked.jpg" alt="Checkbox not checked"></td></tr><tr><td width="8%" class="tableClassValign">13</td><td width="92%" class="tableClass">Percent of class represented by amount in Row (11)
				<br><br><div class="text">6.6 % </div></td></tr><tr><td width="8%" class="tableClassValign">14</td><td width="92%" class="tableClass">Type of Reporting Person (See Instructions)
				<br><br><div class="text">PN</div></td></tr></table><br><div style="display: flex;"><div style="font-size: 0.9em; font-weight: bold; margin-right: 5px;">
					Comment for Type of Reporting Person:
				</div><div class="largetext" style="text-align:justify">(1) The information in Item 5(a) relating to the shares of Common Stock that are or may be deemed beneficially owned by RBI II and the calculation of the percent of such class of securities is incorporated by reference herein.</div></div><table><tr><td class="center"><br><br><p><div align="center" style="font-size:1.2em;">
									SCHEDULE 13D
								</div></p></td></tr></table><table role="presentation" class="tableClass" id="cusipNumber"><tr class="tableClass"><td width="7%" style="font-weight:bold;">CUSIP Number(s):</td><td width="75%"><div style="font-size:.9em; color:#000000">046513206</div></td></tr></table><br><br><table role="presentation" class="tableClass" id="reportingPersonDetails"><tr class="tableClass"><td width="8%" class="tableClassValign">1</td><td width="92%" class="tableClass">
					Name of reporting person
					<br><br><div class="text">Redmile Strategic Long Only Trading Sub, Ltd.</div></td></tr><tr><td width="8%" class="tableClassValign">2</td><td width="92%" class="tableClass">Check the appropriate box if a member of a Group (See Instructions)
				<br><br><div class="text"><img src="/Images/box-unchecked.jpg" alt="Checkbox not checked">  (a)
					<br><img src="/Images/box-unchecked.jpg" alt="Checkbox not checked">  (b)	
				</div></td></tr><tr class="tableClassWithBgBlack"><td width="8%" class="tableClassValign">3</td><td width="92%" class="tableClass">SEC use only</td></tr><tr><td width="8%" class="tableClassValign">4</td><td width="92%" class="tableClass">
					Source of funds (See Instructions)
					<br><br><div class="text">WC</div></td></tr><tr><td width="8%" class="tableClassValign">5</td><td width="92%" class="tableClass">
					Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)
					<br><br><img src="/Images/box-unchecked.jpg" alt="Checkbox not checked"></td></tr><tr><td width="8%" class="tableClassValign">6</td><td width="92%" class="tableClass">Citizenship or place of organization
				<br><br><div class="text">
				CAYMAN ISLANDS
			</div></td></tr><tr><td width="8%" class="tableClassValign">Number of Shares Beneficially Owned by Each Reporting Person With:</td><td width="92%" class="tableClass"><table class="innerTableClass"><tr><td width="8%" class="innerTableClassRightValign">7</td><td width="92%" class="tableClassInnerLeft">Sole Voting Power
							<br><br><div class="text">0.00</div></td></tr><tr><td width="8%" class="innerTableClassRightValign">8</td><td width="92%" class="tableClassInnerLeft">Shared Voting Power
							<br><br><div class="text">401,901.00</div></td></tr><tr><td width="8%" class="innerTableClassRightValign">9</td><td width="92%" class="tableClassInnerLeft">Sole Dispositive Power
							<br><br><div class="text">0.00</div></td></tr><tr><td width="8%" class="innerTableClassRightValignBottomLess">10</td><td width="92%" class="tableClassInnerLeftBottomLess">Shared Dispositive Power
							<br><br><div class="text">401,901.00</div></td></tr></table></td></tr><tr><td width="8%" class="tableClassValign">11</td><td width="92%" class="tableClass">Aggregate amount beneficially owned by each reporting person
				<br><br><div class="text">401,901.00</div></td></tr><tr><td width="8%" class="tableClassValign">12</td><td width="92%" class="tableClass">Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)
				<br><br><img src="/Images/box-unchecked.jpg" alt="Checkbox not checked"></td></tr><tr><td width="8%" class="tableClassValign">13</td><td width="92%" class="tableClass">Percent of class represented by amount in Row (11)
				<br><br><div class="text">4.2 % </div></td></tr><tr><td width="8%" class="tableClassValign">14</td><td width="92%" class="tableClass">Type of Reporting Person (See Instructions)
				<br><br><div class="text">CO</div></td></tr></table><br><div style="display: flex;"><div style="font-size: 0.9em; font-weight: bold; margin-right: 5px;">
					Comment for Type of Reporting Person:
				</div><div class="largetext" style="text-align:justify">(1) The information in Item 5(a) relating to the shares of Common Stock that are or may be deemed beneficially owned by Redmile Long Only and the calculation of the percent of such class of securities is incorporated by reference herein.</div></div></div><div class="form1"><table><tr><td class="center"><br><br><p><div align="center" style="font-size:1.2em;">
									SCHEDULE 13D
								</div></p></td></tr></table><table role="presentation" id="item1to7"><tr><td width="8%" class="tableClassValignNoBorder">Item 1.</td><td width="92%" class="tableClassNoBorder">Security and Issuer</td></tr><tr class="tableClass"><td width="8%" class="tableClassNoBorderAlignCenter">(a)</td><td width="92%" class="tableClassNoBorder">Title of Class of Securities:
							<br><br><div class="text">Common Stock, par value $0.0001 per share</div></td></tr><tr class="tableClass"><td width="8%" class="tableClassNoBorderAlignCenter">(b)</td><td width="92%" class="tableClassNoBorder">Name of Issuer:
							<br><br><div class="text">Atara Biotherapeutics, Inc.</div></td></tr><tr><td width="8%" class="tableClassNoBorderAlignCenter">(c)</td><td width="92%" class="tableClassNoBorder">Address of Issuer's Principal Executive Offices:
							<br><br><div class="text">1280 Rancho Conejo Blvd, Thousand Oaks, 
				CALIFORNIA
			, 91320.</div></td></tr><tr><td width="8%" class="tableClassValignNoBorder">Item 2.</td><td width="92%" class="tableClassNoBorder">Identity and Background</td></tr><tr></tr><tr class="tableClass"><td width="8%" class="tableClassNoBorderAlignCenter">(a)</td><td width="92%" class="tableClassNoBorder"><div class="largetext">This Amendment No. 3 to Schedule 13D (this "Amendment") amends and supplements the Schedule 13D filed with the SEC on May 23, 2025, which was previously amended and supplemented by that Amendment No. 1 to Schedule 13D filed with the SEC on November 14, 2025 and that Amendment No. 2 to Schedule 13D filed with the SEC on May 14, 2026 (collectively, the "Prior Schedule 13D").

This Amendment reports the exercise of certain pre-funded warrants to purchase Common Stock (the "Warrants") by Redmile Strategic Long Only Trading Sub, Ltd. ("Redmile Long Only") and Redmile Biopharma investments II, L.P. ("RBI II" and collectively with Redmile Long Only, Redmile Group, LLC and Jeremy Green, the "Reporting Persons") described in Item 5(a) below and the resulting change in the beneficial ownership of Redmile Long Only following such exercise.

Capitalized terms used but not defined in this Amendment shall have the meanings set forth in the Prior Schedule 13D. Except as specifically amended by this Amendment, the Prior Schedule 13D is unchanged.</div></td></tr><tr><td width="8%" class="tableClassValignNoBorder">Item 3.</td><td width="92%" class="tableClassNoBorder">Source and Amount of Funds or Other Consideration</td></tr><tr><td width="8%" class="tableClassNoBorderAlignCenter"> </td><td width="92%" class="tableClassNoBorder"><div class="largetext">On July 16, 2026, Redmile Group, LLC ("Redmile") exercised certain Warrants held by RBI II and Redmile Long Only through a "cashless exercise" to acquire the Issuer's Common Stock. The transactions resulted in the Issuer (i) withholding 53 shares of Common Stock from RBI II and 7 shares of Common Stock from Redmile Long Only to pay the exercise price under the terms of the Warrants and (ii) issuing the remaining 174,247 shares of Common Stock to RBI II and 20,904 shares of Common Stock to Redmile Long Only.</div></td></tr><tr><td width="8%" class="tableClassValignNoBorder">Item 5.</td><td width="92%" class="tableClassNoBorder">Interest in Securities of the Issuer</td></tr><tr><td width="8%" class="tableClassNoBorderAlignCenter">(a)</td><td width="92%" class="tableClassNoBorder"><div class="largetext">Item 5(a) of the Prior Schedule 13D is hereby amended and restated in its entirety as follows:

The aggregate amount of shares of Common Stock that may be deemed beneficially owned by the Reporting Persons is comprised of (i) 636,852 shares of Common Stock held by certain investment vehicles for which Redmile is the investment manager (the "Redmile Funds"), including the 316,878 shares of Common Stock directly held by RBI II and the 87,759 shares of Common Stock directly held by Redmile Long Only, and (ii) 314,142 shares of Common Stock issuable to the Redmile Funds, including RBI II and Redmile Long Only, upon exercise of certain Warrants, which is the maximum number of shares of Common Stock that could be issued upon exercise of the Warrants under the 9.99% beneficial ownership limitation (the "Beneficial Ownership Limitation"). The Redmile Funds hold Warrants that may be exercised into 3,217,632 shares of Common Stock issuable upon exercise of the Warrants, including the 1,879,855 shares of Common Stock issuable upon exercise of the remaining Warrants directly held by RBI II, and the 806,670 shares of Common Stock issuable upon exercise of the remaining Warrants directly held by Redmile Long Only, each of which is subject to the Beneficial Ownership Limitation. All of the reported securities are directly owned by certain Redmile Funds, including RBI II and Redmile Long Only. Redmile may be deemed to beneficially own these securities in its capacity as their investment manager with discretion to vote and dispose of the securities held by the Redmile Funds. Mr. Green also may be deemed to beneficially own these securities as the principal of Redmile. Redmile and Mr. Green each disclaim beneficial ownership of these securities, except to the extent of its or his pecuniary interest in such securities, if any.

Percentage based on the sum of: (i) 9,010,172 shares of Common Stock outstanding as of May 8, 2026, as reported by the Issuer in its Form 10-Q for the quarterly period ended March 31, 2026 filed with the Securities and Exchange Commission on May 12, 2026, plus (ii) 195,151 shares of Common Stock issued to RBI II and Redmile Long Only upon exercise of certain Warrants, plus (iii) 314,142 shares of Common Stock issuable upon exercise of certain Warrants directly held by the Redmile Funds, which due to the Beneficial Ownership Limitation is the maximum number of shares that could be issued upon exercise of those Warrants.</div></td></tr><tr><td width="8%" class="tableClassNoBorderAlignCenter">(b)</td><td width="92%" class="tableClassNoBorder"><div class="largetext">Item 5(b) of the Prior Schedule 13D is hereby amended and restated in its entirety as follows:

Redmile:

(1) Sole Voting Power: 0
(2) Shared Voting Power: 950,994
(3) Sole Dispositive Power: 0
(4) Shared Dispositive Power: 950,994

Jeremy C. Green:

(1) Sole Voting Power: 0
(2) Shared Voting Power: 950,994
(3) Sole Dispositive Power: 0
(4) Shared Dispositive Power: 950,994

RBI II:

(1) Sole Voting Power: 0
(2) Shared Voting Power: 631,020
(3) Sole Dispositive Power: 0
(4) Shared Dispositive Power: 631,020

Redmile Long Only:

(1) Sole Voting Power: 0
(2) Shared Voting Power: 401,901
(3) Sole Dispositive Power: 0
(4) Shared Dispositive Power: 401,901</div></td></tr><tr><td width="8%" class="tableClassNoBorderAlignCenter">(c)</td><td width="92%" class="tableClassNoBorder"><div class="largetext">See the response to Item 3. Except as disclosed in Item 3, no reportable transactions were effected by any Reporting Persons during the past sixty days.</div></td></tr><tr><td width="8%" class="tableClassNoBorderAlignCenter">(e)</td><td width="92%" class="tableClassNoBorder"><div class="largetext">Redmile Long Only ceased to be a 5% beneficial owner on July 22, 2026 solely as a result of the  exercise of the pre-funded warrants described in Item 3 above.</div></td></tr></table><br></div><div class="form1"><table role="presentation" id="signatureInfo"><tr><td width="8%" class="tableClassValignNoBorder">    SIGNATURE</td><td width="92%" class="tableClassNoBorder"> </td></tr><tr><td width="8%" class="tableClassNoBorderAlignCenter"> </td><td width="92%" class="tableClassNoBorder"><div class="information" style="text-align:justify">
						After reasonable 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.
						<br><br></div></td></tr></table><table><tr class="tableClass"><td width="50%" class="tableClassNoBorder"> </td><td width="50%" class="tableClassNoBorder"><table><tr class="tableClass"><td width="100%" class="tableClassInnerNoBorderBlue"><div class="text">Redmile Group, LLC</div></td></tr></table></td></tr></table><table><tr class="tableClass"><td width="50%" class="tableClassNoBorder"> </td><td width="50%" class="tableClassNoBorder"><table><tr class="tableClass"><td width="8%" class="tableClassNoBorderAlignLeft signature">Signature:</td><td width="92%" class="tableClassNoBorderBlue signature">/s/ Jeremy C. Green</td></tr><tr class="tableClass"><td width="8%" class="tableClassNoBorderAlignLeft signature">Name/Title:</td><td width="92%" class="tableClassNoBorderBlue signature">Managing Member</td></tr><tr class="tableClass"><td width="8%" class="tableClassNoBorderAlignLeft signature">Date:</td><td width="92%" class="tableClassNoBorderBlue signature">07/24/2026</td></tr></table></td></tr></table><table><tr class="tableClass"><td width="50%" class="tableClassNoBorder"> </td><td width="50%" class="tableClassNoBorder"><table><tr class="tableClass"><td width="100%" class="tableClassInnerNoBorderBlue"><div class="text">Green Jeremy</div></td></tr></table></td></tr></table><table><tr class="tableClass"><td width="50%" class="tableClassNoBorder"> </td><td width="50%" class="tableClassNoBorder"><table><tr class="tableClass"><td width="8%" class="tableClassNoBorderAlignLeft signature">Signature:</td><td width="92%" class="tableClassNoBorderBlue signature">/s/ Jeremy C. Green</td></tr><tr class="tableClass"><td width="8%" class="tableClassNoBorderAlignLeft signature">Name/Title:</td><td width="92%" class="tableClassNoBorderBlue signature">Jeremy C. Green</td></tr><tr class="tableClass"><td width="8%" class="tableClassNoBorderAlignLeft signature">Date:</td><td width="92%" class="tableClassNoBorderBlue signature">07/24/2026</td></tr></table></td></tr></table><table><tr class="tableClass"><td width="50%" class="tableClassNoBorder"> </td><td width="50%" class="tableClassNoBorder"><table><tr class="tableClass"><td width="100%" class="tableClassInnerNoBorderBlue"><div class="text">Redmile Biopharma Investments II, L.P.</div></td></tr></table></td></tr></table><table><tr class="tableClass"><td width="50%" class="tableClassNoBorder"> </td><td width="50%" class="tableClassNoBorder"><table><tr class="tableClass"><td width="8%" class="tableClassNoBorderAlignLeft signature">Signature:</td><td width="92%" class="tableClassNoBorderBlue signature">/s/ Jeremy C. Green</td></tr><tr class="tableClass"><td width="8%" class="tableClassNoBorderAlignLeft signature">Name/Title:</td><td width="92%" class="tableClassNoBorderBlue signature">Managing Member of Redmile Biopharma Investments II (GP), LLC, general partner of Redmile Biopharma Investments II, L.P.</td></tr><tr class="tableClass"><td width="8%" class="tableClassNoBorderAlignLeft signature">Date:</td><td width="92%" class="tableClassNoBorderBlue signature">07/24/2026</td></tr></table></td></tr></table><table><tr class="tableClass"><td width="50%" class="tableClassNoBorder"> </td><td width="50%" class="tableClassNoBorder"><table><tr class="tableClass"><td width="100%" class="tableClassInnerNoBorderBlue"><div class="text">Redmile Strategic Long Only Trading Sub, Ltd.</div></td></tr></table></td></tr></table><table><tr class="tableClass"><td width="50%" class="tableClassNoBorder"> </td><td width="50%" class="tableClassNoBorder"><table><tr class="tableClass"><td width="8%" class="tableClassNoBorderAlignLeft signature">Signature:</td><td width="92%" class="tableClassNoBorderBlue signature">/s/ Jeremy C. Green</td></tr><tr class="tableClass"><td width="8%" class="tableClassNoBorderAlignLeft signature">Name/Title:</td><td width="92%" class="tableClassNoBorderBlue signature">Managing Member of Redmile Group, LLC, investment manager of Redmile Strategic Long Only Trading Sub, Ltd.</td></tr><tr class="tableClass"><td width="8%" class="tableClassNoBorderAlignLeft signature">Date:</td><td width="92%" class="tableClassNoBorderBlue signature">07/24/2026</td></tr></table></td></tr></table></div></div>
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