A monoclonal antibody that specifically binds to PCSK9 comprising a) a light chain complementarity determining region of the CDRL1 sequence in SEQ ID NO:23, a CDRL2 of the CDRL2 sequence in SEQ ID NO:23, and a CDRL3 of the CDRL3 sequence in SEQ ID NO:23; and a heavy chain complementarity determining region of the CDRH1 sequence in SEQ ID NO:49, a CDRH2 of the CDRH2 sequence in SEQ ID NO:49, and a CDRH3 of the CDRH3 sequence in SEQ ID NO:49; wherein the CDRs are defined by Chothia or AbM; b) a light chain complementarity determining region CDRL1 comprising the amino acid sequence of SEQ ID NO: 158, a CDRL2 comprising the amino acid sequence of SEQ ID NO: 162, a CDRL3 comprising the amino acid sequence of SEQ ID NO: 395; and a heavy chain complementarity determining region CDRH1 comprising the amino acid sequence of SEQ ID NO: 368, a CDRH2 comprising the amino acid sequence of SEQ ID NO: 175, a CDRH3 comprising the amino acid sequence of SEQ ID NO: 180; c) a light chain complementarity determining region CDRL1 comprising the amino acid sequence of SEQ ID NO: 305, a CDRL2 comprising the amino acid sequence of SEQ ID NO: 312, a CDRL3 comprising the amino acid sequence of SEQ ID NO: 319; and a heavy chain complementarity determining region CDRH1 comprising the amino acid sequence of SEQ ID NO: 308, a CDRH2 comprising the amino acid sequence of SEQ ID NO: 320, a CDRH3 comprising the amino acid sequence of SEQ ID NO: 310; or d) a light chain variable region that comprises the amino acid sequence of SEQ ID NO: 23 and a heavy chain variable region comprises the amino acid sequence of SEQ ID NO:49 for use in (i) lowering serum LDL cholesterol in a human patient by at least 15%; and/or (ii) treating or preventing a cholesterol related disorder in a human patient having an elevated serum LDL cholesterol level; comprising administering the monoclonal antibody to the human patient in need thereof at a dose of 70 mg to 450 mg. a) a light chain complementarity determining region of the CDRL1 sequence in SEQ ID NO:23, a CDRL2 of the CDRL2 sequence in SEQ ID NO:23, and a CDRL3 of the CDRL3 sequence in SEQ ID NO:23; and a heavy chain complementarity determining region of the CDRH1 sequence in SEQ ID NO:49, a CDRH2 of the CDRH2 sequence in SEQ ID NO:49, and a CDRH3 of the CDRH3 sequence in SEQ ID NO:49; wherein the CDRs are defined by Chothia or AbM; b) a light chain complementarity determining region CDRL1 comprising the amino acid sequence of SEQ ID NO: 158, a CDRL2 comprising the amino acid sequence of SEQ ID NO: 162, a CDRL3 comprising the amino acid sequence of SEQ ID NO: 395; and a heavy chain complementarity determining region CDRH1 comprising the amino acid sequence of SEQ ID NO: 368, a CDRH2 comprising the amino acid sequence of SEQ ID NO: 175, a CDRH3 comprising the amino acid sequence of SEQ ID NO: 180; c) a light chain complementarity determining region CDRL1 comprising the amino acid sequence of SEQ ID NO: 305, a CDRL2 comprising the amino acid sequence of SEQ ID NO: 312, a CDRL3 comprising the amino acid sequence of SEQ ID NO: 319; and a heavy chain complementarity determining region CDRH1 comprising the amino acid sequence of SEQ ID NO: 308, a CDRH2 comprising the amino acid sequence of SEQ ID NO: 320, a CDRH3 comprising the amino acid sequence of SEQ ID NO: 310; or d) a light chain variable region that comprises the amino acid sequence of SEQ ID NO: 23 and a heavy chain variable region comprises the amino acid sequence of SEQ ID NO:49 (i) lowering serum LDL cholesterol in a human patient by at least 15%; and/or (ii) treating or preventing a cholesterol related disorder in a human patient having an elevated serum LDL cholesterol level;