diff --git a/.github/workflows/coreneuron-ci.yml b/.github/workflows/coreneuron-ci.yml
index dfddecdff..18285818d 100644
--- a/.github/workflows/coreneuron-ci.yml
+++ b/.github/workflows/coreneuron-ci.yml
@@ -34,9 +34,9 @@ jobs:
         os: [ ubuntu-18.04, macOS-10.15 ]
         config:
           # Defaults: CORENRN_ENABLE_MPI=ON
-          - {cmake_option: "-DCORENRN_ENABLE_MPI=ON -DCORENRN_ENABLE_DEBUG_CODE=ON", documentation: ON}
-          - {cmake_option: "-DCORENRN_ENABLE_MPI_DYNAMIC=ON"}
-          - {cmake_option: "-DCORENRN_ENABLE_MPI_DYNAMIC=ON -DCORENRN_ENABLE_SHARED=OFF"}
+          - {cmake_option: "-DCORENRN_ENABLE_DEBUG_CODE=ON -DTEST_EXEC_PREFIX='mpiexec;-n;2'", documentation: ON}
+          - {cmake_option: "-DCORENRN_ENABLE_MPI_DYNAMIC=ON -DTEST_EXEC_PREFIX='mpiexec;-n;2'"}
+          - {cmake_option: "-DCORENRN_ENABLE_MPI_DYNAMIC=ON -DCORENRN_ENABLE_SHARED=OFF -DTEST_EXEC_PREFIX='mpiexec;-n;2'"}
           - {cmake_option: "-DCORENRN_ENABLE_MPI=OFF"}
           - {use_nmodl: ON, py_version: 3.6.7}
           - {use_nmodl: ON}
diff --git a/README.md b/README.md
index 3d8ce4aca..f8af67f78 100644
--- a/README.md
+++ b/README.md
@@ -321,7 +321,6 @@ If you have a different mpi launcher (than `mpirun`), you can specify it during
 
 ```bash
 cmake .. -DTEST_MPI_EXEC_BIN="mpirun" \
-         -DTEST_EXEC_PREFIX="mpirun;-n;2" \
          -DTEST_EXEC_PREFIX="mpirun;-n;2" \
          -DAUTO_TEST_WITH_SLURM=OFF \
          -DAUTO_TEST_WITH_MPIEXEC=OFF \
diff --git a/tests/integration/CMakeLists.txt b/tests/integration/CMakeLists.txt
index e07a4ebc4..e8aa4d913 100644
--- a/tests/integration/CMakeLists.txt
+++ b/tests/integration/CMakeLists.txt
@@ -117,7 +117,7 @@ foreach(args_line ${TEST_CASES_WITH_ARGS})
       string(REPLACE ";" " " SRUN_PREFIX "")
     else()
       set(test_num_processors 2)
-      string(REPLACE ";" " " SRUN_PREFIX "${TEST_MPI_EXEC_BIN};-n;${test_num_processors}")
+      string(REPLACE ";" " " SRUN_PREFIX "${TEST_EXEC_PREFIX}")
     endif()
   endif()
   list(GET string_line 0 TEST_NAME)
@@ -137,7 +137,7 @@ foreach(args_line ${NEGATIVE_TEST_CASES})
   set(test_num_processors 1)
   if(MPI_FOUND)
     set(test_num_processors 2)
-    string(REPLACE ";" " " SRUN_PREFIX "${TEST_MPI_EXEC_BIN};-n;${test_num_processors}")
+    string(REPLACE ";" " " SRUN_PREFIX "${TEST_EXEC_PREFIX}")
   endif()
   list(GET string_line 0 TEST_NAME)
   list(GET string_line 1 TEST_ARGS)