The present invention discloses a spray drying process characterized by continuous prepn. and immediate spray drying of a soln. comprising at least one active pharmaceutical ingredient and​/or at least one excipient, and at least one solvent. The said active pharmaceutical ingredient(s) and solvent(s) are combined, alone or along with one or more excipients to form a first suspension. Said suspension is continuously fed to an intensifier pump that pushes said suspension through at least one micro-​reaction chamber and​/or at least one micro-​channel where the suspension's solid(s) component(s) is(are) dissolved into said solvent(s) by high energy mixing / forced contact at micro, nano and mol. level to form a soln. stream. The said soln. stream is then immediately and continuously fed to the spray dryer through at least one atomization nozzle, drying said atomized stream to obtain solid particles and collecting said solid particles. Single component particles or multi-​component particles, particulate amorphous solid dispersion and pharmaceutical compns. are also disclosed. The present invention also discloses amorphous solid dispersions obtained by the method of the invention as well as pharmaceutical compns. contg. the same.