diff --git a/src/backends/cl/ClLayerSupport.hpp b/src/backends/cl/ClLayerSupport.hpp
index 80e8488..314ac4c 100644
--- a/src/backends/cl/ClLayerSupport.hpp
+++ b/src/backends/cl/ClLayerSupport.hpp
@@ -9,8 +9,6 @@
 #include <armnn/Tensor.hpp>
 #include <armnn/ArmNN.hpp>
 
-#include <boost/optional.hpp>
-
 namespace armnn
 {
 
@@ -50,14 +48,14 @@
                                 const TensorInfo& output,
                                 const Convolution2dDescriptor& descriptor,
                                 const TensorInfo& weights,
-                                const boost::optional<TensorInfo>& biases,
+                                const Optional<TensorInfo>& biases,
                                 std::string* reasonIfUnsupported = nullptr);
 
 bool IsDepthwiseConvolutionSupportedCl(const TensorInfo& input,
                                        const TensorInfo& output,
                                        const DepthwiseConvolution2dDescriptor& descriptor,
                                        const TensorInfo& weights,
-                                       const boost::optional<TensorInfo>& biases,
+                                       const Optional<TensorInfo>& biases,
                                        std::string* reasonIfUnsupported = nullptr);
 
 bool IsDivisionSupportedCl(const TensorInfo& input0,