Drug lag, which delays patients' access to medicinal products, is typically associated with pharmaceutical regulations. To shorten drug lag, health authorities may establish new policies to liberalize the regulations, a step that is important in countries, such as Taiwan, with consumer demand for imported novel therapeutic agents. Taiwan's government enacted Articles 38--1 and 38--2 of Regulations for Registration of Medicinal Products to relax the regulatory barriers for new drug submission, thus conditionally exempting the requirement for the Certificate of Pharmaceutical Product (CPP). This study examined whether the enacted regulations reduce submission lag by analyzing the time gap of submission between Taiwan and the United States during 2014--2017. The results indicated that the enacted regulations substantially affected submission lag. Submission lag was significantly shorter for applications not requiring a CPP than those requiring one CPP, which in turn was significantly shorter than those requiring two CPPs. This conclusion can be applied to biological, chemical, non-orphan, and oncology drugs and also applications filed by subsidiary companies, but not orphan drugs and applications filed by contract agents. Among applications requiring one CPP, oncology drugs showed the shortest submission lag. Certain factors, such as clinical studies recruiting over-threshold Taiwanese participants and those performed before the submission of new drug application in the United States, may shorten submission lag. In summary, this study justifies the policy of the exemption from CPP requirements, which supports the hypothesis that relaxing regulatory barriers can reduce submission lag in Taiwan.