The policies of Prime Minister Shinzo Abe and the Bank of Japan will fail to reignite long-term growth because they don't address structural flaws in areas such as labor and immigration, according to the chief investment officer of Allianz Global Investors.

"The effects of this major monetary policy will wear off, and then we're going to be back where we are now," Andreas Utermann said in an interview in Paris. "Anyone investing in Japan now is living on borrowed time." Allianz Global Investors, a unit of Allianz SE, oversees about $424 billion.

The policies dubbed "Abenomics" have so far relied on the first two "arrows" of Abe's plan, namely government spending and BOJ Gov. Haruhiko Kuroda's commitment to achieve 2 percent inflation by increasing money stock. The prime minister has yet to fire his third arrow — changes to the economic structure of Japan to reduce the fiscal burden, boost employment and attract talent from outside.

"Without structural reforms in a major way, reforms in the pension system and in immigration for example, you're not going to get there," Utermann said following a presentation Wednesday. "We need a social crisis to trigger major structural changes. There is no crisis in Japan, therefore no urge to reform."

Abenomics has helped to weaken the yen and boosted exports as the government aims to end 15 years of deflation. The policies have fueled a 65 percent gain in the Topix index since the end of 2011, including a 40 percent advance this year, the best performance among 24 developed-market indexes tracked by Bloomberg.

Utermann said investors should continue to favor equities next year.

"It's risky not to be in risky assets," the CIO said. "Any weakness in risk assets, our view is that that is a continuing buying opportunity."