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            <filer>
                <filerCredentials>
                    <cik>0001697107</cik>
                    <ccc>XXXXXXXX</ccc>
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            </filer>
            <liveTestFlag>LIVE</liveTestFlag>



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            <issuerCik>0001651625</issuerCik>
            <issuerName>AC IMMUNE SA</issuerName>
            <secFileNumber>001-37891</secFileNumber>
            <issuerAddress>
                <ns2:street1>EPFL INNOVATION PARK  Building B  1015 </ns2:street1>
                <ns2:city>Lausanne  </ns2:city>
                <ns2:stateOrCountry>V8</ns2:stateOrCountry>
                <ns2:zipCode>00000</ns2:zipCode>
            </issuerAddress>
            <issuerContactPhone>41213459121</issuerContactPhone>
            <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>ANDREA PFEIFER</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
            <relationshipsToIssuer>
                <relationshipToIssuer>Officer</relationshipToIssuer>
            </relationshipsToIssuer>
        </issuerInfo>
        <securitiesInformation>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <brokerOrMarketmakerDetails>
                <name>Morgan Stanley Smith Barney LLC Executive Financial Services</name>
                <address>
                    <ns2:street1>1 New York Plaza</ns2:street1>
                    <ns2:street2>38th Fl.</ns2:street2>
                    <ns2:city>New York</ns2:city>
                    <ns2:stateOrCountry>NY</ns2:stateOrCountry>
                    <ns2:zipCode>10004</ns2:zipCode>
                </address>
            </brokerOrMarketmakerDetails>
            <noOfUnitsSold>20000</noOfUnitsSold>
            <aggregateMarketValue>73800.00</aggregateMarketValue>
            <noOfUnitsOutstanding>83620364</noOfUnitsOutstanding>
            <approxSaleDate>12/11/2023</approxSaleDate>
            <securitiesExchangeName>NASDAQ</securitiesExchangeName>
        </securitiesInformation>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>06/01/2012</acquiredDate>
            <natureOfAcquisitionTransaction>Series B Pref. shares	</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>20000</amountOfSecuritiesAcquired>
            <paymentDate>06/01/2012</paymentDate>
            <natureOfPayment>N/A</natureOfPayment>
        </securitiesToBeSold>
        <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>10b5-1 Sales for ANDREA PFEIFER</name>
                <address>
                    <ns2:street1>EPFL INNOVATION PARK  Building B  1015 </ns2:street1>
                    <ns2:city>Lausanne  </ns2:city>
                    <ns2:stateOrCountry>V8</ns2:stateOrCountry>
                    <ns2:zipCode>00000</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>12/07/2023</saleDate>
            <amountOfSecuritiesSold>5168</amountOfSecuritiesSold>
            <grossProceeds>18901.96</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>10b5-1 Sales for ANDREA PFEIFER</name>
                <address>
                    <ns2:street1>EPFL INNOVATION PARK  Building B  1015 </ns2:street1>
                    <ns2:city>Lausanne  </ns2:city>
                    <ns2:stateOrCountry>V8</ns2:stateOrCountry>
                    <ns2:zipCode>00000</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>12/06/2023</saleDate>
            <amountOfSecuritiesSold>14832</amountOfSecuritiesSold>
            <grossProceeds>53647.34</grossProceeds>
        </securitiesSoldInPast3Months>
        <noticeSignature>
            <noticeDate>12/11/2023</noticeDate>
            <planAdoptionDates>
                <planAdoptionDate>03/31/2023</planAdoptionDate>
            </planAdoptionDates>
            <signature>/s/ Andrea Pfeifer</signature>
        </noticeSignature>
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144
0001697107
XXXXXXXX
LIVE
0001651625
AC IMMUNE SA
001-37891
EPFL INNOVATION PARK  Building B  1015
Lausanne
V8
00000
41213459121
ANDREA PFEIFER
Officer
Common
Morgan Stanley Smith Barney LLC Executive Financial Services
1 New York Plaza
38th Fl.
New York
NY
10004
20000
73800.00
83620364
12/11/2023
NASDAQ
Common
06/01/2012
Series B Pref. shares
Issuer
N
20000
06/01/2012
N/A
N
10b5-1 Sales for ANDREA PFEIFER
EPFL INNOVATION PARK  Building B  1015
Lausanne
V8
00000
Common
12/07/2023
5168
18901.96
10b5-1 Sales for ANDREA PFEIFER
EPFL INNOVATION PARK  Building B  1015
Lausanne
V8
00000
Common
12/06/2023
14832
53647.34
12/11/2023
03/31/2023
/s/ Andrea Pfeifer