What is the effect of an international patent application?

What is the effect of an international patent application?

 PCT National Phase Entry in Vietnam

In general terms, your international patent application, provided that it complies with the minimum requirements for obtaining an international filing date, has the effect of a national patent application (and certain regional patent applications) in or for all PCT Contracting States. Moreover, if you comply with certain formal requirements set out in the Treaty and Regulations, which are binding on all of the PCT Contracting States, subsequent adaptation to varying national (or regional) formal requirements (and the cost associated therewith) will not be necessary.