浩鼎案對我國生技產業股價反應之研究

Abstract

摘 要 過去相關研究結果顯示資訊科技的進步將影響投資人行為（Asthana and Balsam, 2001；Asthana, 2003）會反應在交易量或股價報酬上，本研究透過浩鼎於2016/2/21召開解盲記者會一事，就其說明解肓之結果顯示雖無顯著療效而告失敗，市場一片嘩然，隔日即波及我國生技股股價大幅下跌之事件為引，引發本研究動機。擬採用事件研究法探討下列研究目的：一、從浩鼎重大資訊宣告觀察我國股市中生技股股價變化？二、從浩鼎案觀察新藥試驗訊息宣告是否會對其股價產生影響? 本研究採用事件研究法，分別針對浩鼎公布其最新藥品OBI-822乳癌藥的解盲資訊及各製藥公司與新藥導入人體試驗階段相關資訊之宣告為事件進行研究。實證結果發現，資訊揭露時，股價的確出現異常報酬，且浩鼎解盲結果宣告後，累積平均異常報酬率持續走跌，證實資訊內涵價值存在，且透過事件窗口之結果，顯示我國證券市場可能存在投資人對資訊過度反應（或反應不足）現象。 本研究透過對於各生技新藥公司發布三期臨床試驗訊息之事件資訊檢視發現，其中多數為正向資訊；而企業在臨床試驗階段，重大訊息宣告日存在正的超額報酬與累積異常報酬反應。然而經由實證結果中的事件窗口顯示，累積平均異常報酬率由正轉負，推論資訊內涵並未正確反應在股價走勢上，股價未能完全反應資訊之因素是否與解盲失敗結果於資訊宣告後引發的股價快速下跌，導致投資人對於導入試驗之資訊傾向以負面態度進行判斷，未能證實。 關鍵字：生技製藥、浩鼎、事件研究法、過度反應

ABSTRACT The results of previous research reveal that the progress in technology will affect investors' thoughts and behaviors. (Asthana and Balsam, 2001; Asthana, 2003) It reflects on the trade volume and prices of the stock. This research is based on the press conference for Unblind held on 2016/2/21 by OBI Pharma, Inc., The failure of Unblind research resulting in the plunge of stock prices in biomedical companies brought up the motivation for this study. The following 2 objectives will be discussed through event study. 1. Observation on the degree of impact on stock prices of biomedical companies by the news like the press release from OBI Pharma, Inc., 2. From the OBI Pharma, Inc., this case, find out if the news about the new medicine will affect stock prices. The research is based on OBI Pharma, Inc., announcement of OBI-822 the medicine for breast cancer and other biomedical companies' release of launching new medicine. According to the survey, unexpectedly high return on stock happened when the announcement was made. The information released by corporations continuously affects stock prices. It is obvious that the investors very much rely on the companies’ news.This research found that most of information announced are positive through the contents companies announced on third stage clinical trial. The stock prices generally go skyrocketed on the day important news announced. However, the stock prices went up and down not necessarily following the news content. Therefore, the plunge in stock prices is not proven to be related to the failure in Unblind.

Keywords: Biotechnology , OBI Pharma Inc , event study, overreaction